51811379136 has 336 divisors, whose sum is σ = 169465191168. Its totient is φ = 15694145280.

The previous prime is 51811379101. The next prime is 51811379159. The reversal of 51811379136 is 63197311815.

51811379136 is a `hidden beast` number, since 518 + 1 + 13 + 7 + 91 + 36 = 666.

It is a super-2 number, since 2×51811379136² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 51811379091 and 51811379100.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 20698461 + ... + 20700963.

It is an arithmetic number, because the mean of its divisors is an integer number (504360688).

Almost surely, 2^51811379136 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51811379136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (84732595584).

51811379136 is an abundant number, since it is smaller than the sum of its proper divisors (117653812032).

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

51811379136 is an equidigital number, since it uses as much as digits as its factorization.

51811379136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2563 (or 2519 counting only the distinct ones).

The product of its digits is 136080, while the sum is 45.

The spelling of 51811379136 in words is "fifty-one billion, eight hundred eleven million, three hundred seventy-nine thousand, one hundred thirty-six".