81615004 has 12 divisors (see below), whose sum is σ = 142921800. Its totient is φ = 40780208.

The previous prime is 81614987. The next prime is 81615031. The reversal of 81615004 is 40051618.

It is a super-2 number, since 2×81615004² = 13322017755840032, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 81615004.

It is a congruent number.

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, 867 + ... + 12805.

It is an arithmetic number, because the mean of its divisors is an integer number (11910150).

Almost surely, 2^81615004 is an apocalyptic number.

It is an amenable number.

81615004 is a deficient number, since it is larger than the sum of its proper divisors (61306796).

81615004 is a wasteful number, since it uses less digits than its factorization.

81615004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13652 (or 13650 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 25.

The square root of 81615004 is about 9034.1022796955. The cubic root of 81615004 is about 433.7671597493.

The spelling of 81615004 in words is "eighty-one million, six hundred fifteen thousand, four".