91581252 has 72 divisors (see below), whose sum is σ = 249133248. Its totient is φ = 25649280.

The previous prime is 91581251. The next prime is 91581257. The reversal of 91581252 is 25218519.

It is a hoax number, since the sum of its digits (33) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (91581251) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 312418 + ... + 312710.

It is an arithmetic number, because the mean of its divisors is an integer number (3460184).

Almost surely, 2^91581252 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91581252, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (124566624).

91581252 is an abundant number, since it is smaller than the sum of its proper divisors (157551996).

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

91581252 is a wasteful number, since it uses less digits than its factorization.

91581252 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 429 (or 366 counting only the distinct ones).

The product of its digits is 7200, while the sum is 33.

The square root of 91581252 is about 9569.8094024907. The cubic root of 91581252 is about 450.7497821311.

The spelling of 91581252 in words is "ninety-one million, five hundred eighty-one thousand, two hundred fifty-two".