251387765020 has 24 divisors (see below), whose sum is σ = 603330636384. Its totient is φ = 86190090816.

The previous prime is 251387765011. The next prime is 251387765129. The reversal of 251387765020 is 20567783152.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 897813307 + ... + 897813586.

It is an arithmetic number, because the mean of its divisors is an integer number (25138776516).

Almost surely, 2^251387765020 is an apocalyptic number.

251387765020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

251387765020 is an abundant number, since it is smaller than the sum of its proper divisors (351942871364).

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

251387765020 is a wasteful number, since it uses less digits than its factorization.

251387765020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1795626909 (or 1795626907 counting only the distinct ones).

The product of its (nonzero) digits is 705600, while the sum is 46.

The spelling of 251387765020 in words is "two hundred fifty-one billion, three hundred eighty-seven million, seven hundred sixty-five thousand, twenty".