81519264 has 48 divisors (see below), whose sum is σ = 237767040. Its totient is φ = 27172800.

The previous prime is 81519259. The next prime is 81519281. The reversal of 81519264 is 46291518.

81519264 is a `hidden beast` number, since 81 + 519 + 2 + 64 = 666.

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 46312 + ... + 48039.

It is an arithmetic number, because the mean of its divisors is an integer number (4953480).

Almost surely, 2^81519264 is an apocalyptic number.

It is an amenable number.

81519264 is an abundant number, since it is smaller than the sum of its proper divisors (156247776).

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

81519264 is a wasteful number, since it uses less digits than its factorization.

81519264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94370 (or 94356 counting only the distinct ones).

The product of its digits is 17280, while the sum is 36.

The square root of 81519264 is about 9028.8019138754. The cubic root of 81519264 is about 433.5974805026.

The spelling of 81519264 in words is "eighty-one million, five hundred nineteen thousand, two hundred sixty-four".