81887090764 has 96 divisors (see below), whose sum is σ = 159466418496. Its totient is φ = 36632494080.

The previous prime is 81887090743. The next prime is 81887090771. The reversal of 81887090764 is 46709078818.

It is a junction number, because it is equal to n+sod(n) for n = 81887090699 and 81887090708.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 17298942 + ... + 17303674.

It is an arithmetic number, because the mean of its divisors is an integer number (1661108526).

Almost surely, 2^81887090764 is an apocalyptic number.

It is an amenable number.

81887090764 is a deficient number, since it is larger than the sum of its proper divisors (77579327732).

81887090764 is a wasteful number, since it uses less digits than its factorization.

81887090764 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4955 (or 4953 counting only the distinct ones).

The product of its (nonzero) digits is 5419008, while the sum is 58.

The spelling of 81887090764 in words is "eighty-one billion, eight hundred eighty-seven million, ninety thousand, seven hundred sixty-four".