81880513516 has 12 divisors (see below), whose sum is σ = 143922137688. Its totient is φ = 40759902752.

The previous prime is 81880513501. The next prime is 81880513553. The reversal of 81880513516 is 61531508818.

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, 45087481 + ... + 45089296.

It is an arithmetic number, because the mean of its divisors is an integer number (11993511474).

Almost surely, 2^81880513516 is an apocalyptic number.

It is an amenable number.

81880513516 is a deficient number, since it is larger than the sum of its proper divisors (62041624172).

81880513516 is a wasteful number, since it uses less digits than its factorization.

81880513516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90177008 (or 90177006 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 46.

The spelling of 81880513516 in words is "eighty-one billion, eight hundred eighty million, five hundred thirteen thousand, five hundred sixteen".