51439981086 has 24 divisors (see below), whose sum is σ = 120026623080. Its totient is φ = 15827686416.

The previous prime is 51439981069. The next prime is 51439981121. The reversal of 51439981086 is 68018993415.

51439981086 is a `hidden beast` number, since 51 + 439 + 9 + 81 + 0 + 86 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 109914256 + ... + 109914723.

It is an arithmetic number, because the mean of its divisors is an integer number (5001109295).

Almost surely, 2^51439981086 is an apocalyptic number.

51439981086 is an abundant number, since it is smaller than the sum of its proper divisors (68586641994).

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

51439981086 is a wasteful number, since it uses less digits than its factorization.

51439981086 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 219829000 (or 219828997 counting only the distinct ones).

The product of its (nonzero) digits is 1866240, while the sum is 54.

The spelling of 51439981086 in words is "fifty-one billion, four hundred thirty-nine million, nine hundred eighty-one thousand, eighty-six".