721625256 has 192 divisors, whose sum is σ = 2221914240. Its totient is φ = 209664000.

The previous prime is 721625239. The next prime is 721625257. The reversal of 721625256 is 652526127.

721625256 is a `hidden beast` number, since 7 + 2 + 1 + 625 + 25 + 6 = 666.

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

It is a self number, because there is not a number n which added to its sum of digits gives 721625256.

It is not an unprimeable number, because it can be changed into a prime (721625257) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2305356 + ... + 2305668.

It is an arithmetic number, because the mean of its divisors is an integer number (11572470).

Almost surely, 2^721625256 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 721625256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1110957120).

721625256 is an abundant number, since it is smaller than the sum of its proper divisors (1500288984).

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

721625256 is a wasteful number, since it uses less digits than its factorization.

721625256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 448 (or 441 counting only the distinct ones).

The product of its digits is 50400, while the sum is 36.

The square root of 721625256 is about 26863.0835162310. The cubic root of 721625256 is about 896.9548341744.

The spelling of 721625256 in words is "seven hundred twenty-one million, six hundred twenty-five thousand, two hundred fifty-six".