251651412720 has 60 divisors (see below), whose sum is σ = 845129330136. Its totient is φ = 67107043200.

The previous prime is 251651412703. The next prime is 251651412821. The reversal of 251651412720 is 27214156152.

251651412720 is a `hidden beast` number, since 2 + 5 + 16 + 514 + 127 + 2 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (60).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 174757206 + ... + 174758645.

Almost surely, 2^251651412720 is an apocalyptic number.

251651412720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

251651412720 is an abundant number, since it is smaller than the sum of its proper divisors (593477917416).

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

251651412720 is a wasteful number, since it uses less digits than its factorization.

251651412720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 349515870 (or 349515861 counting only the distinct ones).

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

Adding to 251651412720 its reverse (27214156152), we get a palindrome (278865568872).

The spelling of 251651412720 in words is "two hundred fifty-one billion, six hundred fifty-one million, four hundred twelve thousand, seven hundred twenty".