251925991680 has 576 divisors, whose sum is σ = 934575667200. Its totient is φ = 57192284160.

The previous prime is 251925991657. The next prime is 251925991721. The reversal of 251925991680 is 86199529152.

It is a Harshad number since it is a multiple of its sum of digits (57).

It is a self number, because there is not a number n which added to its sum of digits gives 251925991680.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 71426077 + ... + 71429603.

It is an arithmetic number, because the mean of its divisors is an integer number (1622527200).

Almost surely, 2^251925991680 is an apocalyptic number.

251925991680 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 251925991680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (467287833600).

251925991680 is an abundant number, since it is smaller than the sum of its proper divisors (682649675520).

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

251925991680 is a wasteful number, since it uses less digits than its factorization.

251925991680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3670 (or 3656 counting only the distinct ones).

The product of its (nonzero) digits is 3499200, while the sum is 57.

The spelling of 251925991680 in words is "two hundred fifty-one billion, nine hundred twenty-five million, nine hundred ninety-one thousand, six hundred eighty".