91721268 has 24 divisors (see below), whose sum is σ = 237796160. Its totient is φ = 30573720.

The previous prime is 91721257. The next prime is 91721293. The reversal of 91721268 is 86212719.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 424528 + ... + 424743.

Almost surely, 2^91721268 is an apocalyptic number.

It is an amenable number.

91721268 is an abundant number, since it is smaller than the sum of its proper divisors (146074892).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91721268 is a wasteful number, since it uses less digits than its factorization.

91721268 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 849284 (or 849276 counting only the distinct ones).

The product of its digits is 12096, while the sum is 36.

The square root of 91721268 is about 9577.1221147065. The cubic root of 91721268 is about 450.9793780506.

It can be divided in two parts, 9172 and 1268, that added together give a triangular number (10440 = T₁₄₄).

The spelling of 91721268 in words is "ninety-one million, seven hundred twenty-one thousand, two hundred sixty-eight".