81506914155192 has 64 divisors (see below), whose sum is σ = 203930989516800. Its totient is φ = 27147152229120.

The previous prime is 81506914155143. The next prime is 81506914155193. The reversal of 81506914155192 is 29155141960518.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81506914155193) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 163298793 + ... + 163797159.

It is an arithmetic number, because the mean of its divisors is an integer number (3186421711200).

Almost surely, 2^{81506914155192} is an apocalyptic number.

It is an amenable number.

81506914155192 is an abundant number, since it is smaller than the sum of its proper divisors (122424075361608).

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

81506914155192 is a wasteful number, since it uses less digits than its factorization.

81506914155192 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 503836 (or 503832 counting only the distinct ones).

The product of its (nonzero) digits is 3888000, while the sum is 57.

The spelling of 81506914155192 in words is "eighty-one trillion, five hundred six billion, nine hundred fourteen million, one hundred fifty-five thousand, one hundred ninety-two".