72640256 has 108 divisors (see below), whose sum is σ = 166079088. Its totient is φ = 31629312.

The previous prime is 72640241. The next prime is 72640283. The reversal of 72640256 is 65204627.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 995036 + ... + 995108.

Almost surely, 2^72640256 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 72640256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83039544).

72640256 is an abundant number, since it is smaller than the sum of its proper divisors (93438832).

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

72640256 is a wasteful number, since it uses less digits than its factorization.

72640256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138 (or 111 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 32.

The square root of 72640256 is about 8522.9253193959. The cubic root of 72640256 is about 417.2462626882.

The spelling of 72640256 in words is "seventy-two million, six hundred forty thousand, two hundred fifty-six".