81879604 has 12 divisors (see below), whose sum is σ = 143498628. Its totient is φ = 40880000.

The previous prime is 81879571. The next prime is 81879617. The reversal of 81879604 is 40697818.

It can be written as a sum of positive squares in 2 ways, for example, as 49730704 + 32148900 = 7052^2 + 5670^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11797 + ... + 17404.

It is an arithmetic number, because the mean of its divisors is an integer number (11958219).

Almost surely, 2^81879604 is an apocalyptic number.

It is an amenable number.

81879604 is a deficient number, since it is larger than the sum of its proper divisors (61619024).

81879604 is a wasteful number, since it uses less digits than its factorization.

81879604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29906 (or 29904 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 43.

The square root of 81879604 is about 9048.7349392056. The cubic root of 81879604 is about 434.2354191483.

The spelling of 81879604 in words is "eighty-one million, eight hundred seventy-nine thousand, six hundred four".