81499536280 has 16 divisors (see below), whose sum is σ = 183373956720. Its totient is φ = 32599814496.

The previous prime is 81499536259. The next prime is 81499536319. The reversal of 81499536280 is 8263599418.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1018744164 + ... + 1018744243.

It is an arithmetic number, because the mean of its divisors is an integer number (11460872295).

Almost surely, 2^81499536280 is an apocalyptic number.

It is an amenable number.

81499536280 is an abundant number, since it is smaller than the sum of its proper divisors (101874420440).

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

81499536280 is a wasteful number, since it uses less digits than its factorization.

81499536280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2037488418 (or 2037488414 counting only the distinct ones).

The product of its (nonzero) digits is 3732480, while the sum is 55.

The spelling of 81499536280 in words is "eighty-one billion, four hundred ninety-nine million, five hundred thirty-six thousand, two hundred eighty".