51381988684 has 72 divisors (see below), whose sum is σ = 101716769952. Its totient is φ = 22657789440.

The previous prime is 51381988673. The next prime is 51381988687. The reversal of 51381988684 is 48688918315.

It is a super-2 number, since 2×51381988684² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (51381988687) 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, 21470592 + ... + 21472984.

It is an arithmetic number, because the mean of its divisors is an integer number (1412732916).

Almost surely, 2^51381988684 is an apocalyptic number.

It is an amenable number.

51381988684 is a deficient number, since it is larger than the sum of its proper divisors (50334781268).

51381988684 is a wasteful number, since it uses less digits than its factorization.

51381988684 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3827 (or 3812 counting only the distinct ones).

The product of its digits is 13271040, while the sum is 61.

The spelling of 51381988684 in words is "fifty-one billion, three hundred eighty-one million, nine hundred eighty-eight thousand, six hundred eighty-four".