81537750087 has 16 divisors (see below), whose sum is σ = 113593758720. Its totient is φ = 51926368032.

The previous prime is 81537750079. The next prime is 81537750143. The reversal of 81537750087 is 78005773518.

It is not a de Polignac number, because 81537750087 - 2³ = 81537750079 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81537750187) 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, 728287 + ... + 832752.

It is an arithmetic number, because the mean of its divisors is an integer number (7099609920).

Almost surely, 2^81537750087 is an apocalyptic number.

81537750087 is a deficient number, since it is larger than the sum of its proper divisors (32056008633).

81537750087 is a wasteful number, since it uses less digits than its factorization.

81537750087 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1561822.

The product of its (nonzero) digits is 1646400, while the sum is 51.

The spelling of 81537750087 in words is "eighty-one billion, five hundred thirty-seven million, seven hundred fifty thousand, eighty-seven".