81499415766 has 32 divisors (see below), whose sum is σ = 163254300000. Its totient is φ = 27123932160.

The previous prime is 81499415737. The next prime is 81499415771. The reversal of 81499415766 is 66751499418.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12144420 + ... + 12151128.

It is an arithmetic number, because the mean of its divisors is an integer number (5101696875).

Almost surely, 2^81499415766 is an apocalyptic number.

81499415766 is an abundant number, since it is smaller than the sum of its proper divisors (81754884234).

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

81499415766 is a wasteful number, since it uses less digits than its factorization.

81499415766 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9584.

The product of its digits is 13063680, while the sum is 60.

The spelling of 81499415766 in words is "eighty-one billion, four hundred ninety-nine million, four hundred fifteen thousand, seven hundred sixty-six".