51818587956 has 72 divisors (see below), whose sum is σ = 133832934144. Its totient is φ = 16897757760.

The previous prime is 51818587937. The next prime is 51818587967. The reversal of 51818587956 is 65978581815.

51818587956 is a `hidden beast` number, since 518 + 18 + 58 + 7 + 9 + 56 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 51818587893 and 51818587902.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4716886 + ... + 4727858.

It is an arithmetic number, because the mean of its divisors is an integer number (1858790752).

Almost surely, 2^51818587956 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 51818587956, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (66916467072).

51818587956 is an abundant number, since it is smaller than the sum of its proper divisors (82014346188).

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

51818587956 is a wasteful number, since it uses less digits than its factorization.

51818587956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13821 (or 13816 counting only the distinct ones).

The product of its digits is 24192000, while the sum is 63.

The spelling of 51818587956 in words is "fifty-one billion, eight hundred eighteen million, five hundred eighty-seven thousand, nine hundred fifty-six".