251309710864 has 45 divisors (see below), whose sum is σ = 509096545293. Its totient is φ = 120169543296.

The previous prime is 251309710849. The next prime is 251309710889. The reversal of 251309710864 is 468017903152.

The square root of 251309710864 is 501308.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 25950632464 + 225359078400 = 161092^2 + 474720^2 .

It is a Harshad number since it is a multiple of its sum of digits (46).

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 46117612 + ... + 46123060.

It is a 1-persistent number, because it is pandigital, but 2⋅251309710864 = 502619421728 is not.

Almost surely, 2^251309710864 is an apocalyptic number.

251309710864 is the 501308-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 251309710864

251309710864 is an abundant number, since it is smaller than the sum of its proper divisors (257786834429).

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

251309710864 is an frugal number, since it uses more digits than its factorization.

251309710864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10952 (or 5474 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 46.

The spelling of 251309710864 in words is "two hundred fifty-one billion, three hundred nine million, seven hundred ten thousand, eight hundred sixty-four".