291 (number)

291 is the natural number following 290 and preceding 292.

← 290 291 292 →
← 200 210 220 230 240 250 260 270 280 290 → List of numbers Integers ← 0 100 200 300 400 500 600 700 800 900 →
Cardinal	two hundred ninety-one
Ordinal	291st (two hundred ninety-first)
Factorization	3 × 97
Divisors	1, 3, 97, 291
Greek numeral	ΣϞΑ´
Roman numeral	CCXCI, ccxci
Binary	1001000112
Ternary	1012103
Senary	12036
Octal	4438
Duodecimal	20312
Hexadecimal	12316

In mathematics

• 291 is an odd composite number with two prime factors.^[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 six 4th powers. It is the sum of 4⁴+2⁴+2⁴+1⁴+1⁴+1⁴.^[5]