251968504320 has 240 divisors, whose sum is σ = 939764898072. Its totient is φ = 62022942720.

The previous prime is 251968504289. The next prime is 251968504321. The reversal of 251968504320 is 23405869152.

251968504320 is a `hidden beast` number, since 2 + 51 + 9 + 68 + 504 + 32 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 207017720064 + 44950784256 = 454992^2 + 212016^2 .

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (251968504321) 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, 121101 + ... + 720140.

Almost surely, 2^251968504320 is an apocalyptic number.

251968504320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 251968504320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (469882449036).

251968504320 is an abundant number, since it is smaller than the sum of its proper divisors (687796393752).

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

251968504320 is a wasteful number, since it uses less digits than its factorization.

251968504320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 841283 (or 841264 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 45.

The spelling of 251968504320 in words is "two hundred fifty-one billion, nine hundred sixty-eight million, five hundred four thousand, three hundred twenty".