51503318138 has 8 divisors (see below), whose sum is σ = 78313264788. Its totient is φ = 25398896544.

The previous prime is 51503318039. The next prime is 51503318161. The reversal of 51503318138 is 83181330515.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 51391529809 + 111788329 = 226697^2 + 10573^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 176381081 + ... + 176381372.

Almost surely, 2^51503318138 is an apocalyptic number.

51503318138 is a deficient number, since it is larger than the sum of its proper divisors (26809946650).

51503318138 is a wasteful number, since it uses less digits than its factorization.

51503318138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 352762528.

The product of its (nonzero) digits is 43200, while the sum is 38.

The spelling of 51503318138 in words is "fifty-one billion, five hundred three million, three hundred eighteen thousand, one hundred thirty-eight".