291 (number)

From Wikipedia, the free encyclopedia
← 290 291 292 →
Cardinaltwo hundred ninety-one
Ordinal291st
(two hundred ninety-first)
Factorization3 × 97
Divisors1, 3, 97, 291
Greek numeralΣϞΑ´
Roman numeralCCXCI
Binary1001000112
Ternary1012103
Senary12036
Octal4438
Duodecimal20312
Hexadecimal12316

291 is the natural number following 290 and preceding 292.

In mathematics[edit]

  • 291 is an odd composite number with two prime factor.[1]
  • 291 is a semiprime number meaning that it has 2 prime factors.[2]
  • 291 can be written as the sum of the nth prime plus n. It is the 52nd prime (239) plus 52.[3]
  • 291 is one of the positions of “c” in the tribonacci word abacabaab… defined by a->ab, b->ac, c->a.[4]
  • 291 is the sum of 6 different 4th powers. It is the sum of 44+24+24+14+14+14.[5]

World Records[edit]

Other fields[edit]

References[edit]

  1. ^ "Facts about the integer". mathworld.wolfram.com.
  2. ^ "Semiprime". mathworld.wolfram.com.
  3. ^ Sloane, N. J. A. (ed.). "Sequence A014688". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
  4. ^ Sloane, N. J. A. (ed.). "Sequence A003146 (Positions of letter c in the tribonacci word abacabaabacababac... generated by a->ab, b->ac, c->a (cf. A092782))". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
  5. ^ Sloane, N. J. A. (ed.). "Sequence A003340 (Numbers that are the sum of 6 positive 4th powers)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
  6. ^ "291 kg elephant bar deadlift". www/guinnessworldrecords.com.
  7. ^ "291 cakes eaten online". www.guinnessworldrecords.com.
  8. ^ "291 m long string instrument". www.guinnessworldrecords.com.
  9. ^ "2.91 m tall usable pogo stick". www.guinnessworldrecords.com.
  10. ^ "291 Alice". www.universguide.com. 27 March 2019.