81137665300 has 18 divisors (see below), whose sum is σ = 176068733918. Its totient is φ = 32455066080.

The previous prime is 81137665247. The next prime is 81137665313. The reversal of 81137665300 is 356673118.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 12083285776 + 69054379524 = 109924^2 + 262782^2 .

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, 405688227 + ... + 405688426.

Almost surely, 2^81137665300 is an apocalyptic number.

It is an amenable number.

81137665300 is an abundant number, since it is smaller than the sum of its proper divisors (94931068618).

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

81137665300 is a wasteful number, since it uses less digits than its factorization.

81137665300 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 811376667 (or 811376660 counting only the distinct ones).

The product of its (nonzero) digits is 90720, while the sum is 40.

The spelling of 81137665300 in words is "eighty-one billion, one hundred thirty-seven million, six hundred sixty-five thousand, three hundred".