81787330986 has 16 divisors (see below), whose sum is σ = 163965060000. Its totient is φ = 27197377328.

The previous prime is 81787330943. The next prime is 81787331023. The reversal of 81787330986 is 68903378718.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16263861 + ... + 16268888.

It is an arithmetic number, because the mean of its divisors is an integer number (10247816250).

Almost surely, 2^81787330986 is an apocalyptic number.

81787330986 is an abundant number, since it is smaller than the sum of its proper divisors (82177729014).

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

81787330986 is a wasteful number, since it uses less digits than its factorization.

81787330986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32533173.

The product of its (nonzero) digits is 12192768, while the sum is 60.

The spelling of 81787330986 in words is "eighty-one billion, seven hundred eighty-seven million, three hundred thirty thousand, nine hundred eighty-six".