72521856 has 192 divisors, whose sum is σ = 233906400. Its totient is φ = 21381120.

The previous prime is 72521849. The next prime is 72521899. The reversal of 72521856 is 65812527.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (192).

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

It is an alternating number because its digits alternate between odd and even.

It is a self number, because there is not a number n which added to its sum of digits gives 72521856.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 747600 + ... + 747696.

Almost surely, 2^72521856 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 72521856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (116953200).

72521856 is an abundant number, since it is smaller than the sum of its proper divisors (161384544).

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

72521856 is a wasteful number, since it uses less digits than its factorization.

72521856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187 (or 172 counting only the distinct ones).

The product of its digits is 33600, while the sum is 36.

The square root of 72521856 is about 8515.9765147633. The cubic root of 72521856 is about 417.0194425315.

The spelling of 72521856 in words is "seventy-two million, five hundred twenty-one thousand, eight hundred fifty-six".