51115651636 has 18 divisors (see below), whose sum is σ = 104056862658. Its totient is φ = 21906707760.

The previous prime is 51115651579. The next prime is 51115651649. The reversal of 51115651636 is 63615651115.

It can be written as a sum of positive squares in only one way, i.e., 48651124900 + 2464526736 = 220570^2 + 49644^2 .

It is a super-2 number, since 2×51115651636² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 130396875 + ... + 130397266.

Almost surely, 2^51115651636 is an apocalyptic number.

It is an amenable number.

51115651636 is an abundant number, since it is smaller than the sum of its proper divisors (52941211022).

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

51115651636 is a wasteful number, since it uses less digits than its factorization.

51115651636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 260794159 (or 260794150 counting only the distinct ones).

The product of its digits is 81000, while the sum is 40.

The spelling of 51115651636 in words is "fifty-one billion, one hundred fifteen million, six hundred fifty-one thousand, six hundred thirty-six".