251267661620 has 48 divisors (see below), whose sum is σ = 562318944768. Its totient is φ = 94091712000.

The previous prime is 251267661607. The next prime is 251267661653. The reversal of 251267661620 is 26166762152.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5789381 + ... + 5832620.

It is an arithmetic number, because the mean of its divisors is an integer number (11714978016).

Almost surely, 2^251267661620 is an apocalyptic number.

251267661620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

251267661620 is an abundant number, since it is smaller than the sum of its proper divisors (311051283148).

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

251267661620 is a wasteful number, since it uses less digits than its factorization.

251267661620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11622080 (or 11622078 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 44.

The spelling of 251267661620 in words is "two hundred fifty-one billion, two hundred sixty-seven million, six hundred sixty-one thousand, six hundred twenty".