21197079804 has 24 divisors (see below), whose sum is σ = 50015584080. Its totient is φ = 6986303104.

The previous prime is 21197079791. The next prime is 21197079821. The reversal of 21197079804 is 40897079112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9922659 + ... + 9924794.

It is an arithmetic number, because the mean of its divisors is an integer number (2083982670).

Almost surely, 2^21197079804 is an apocalyptic number.

It is an amenable number.

21197079804 is an abundant number, since it is smaller than the sum of its proper divisors (28818504276).

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

21197079804 is a wasteful number, since it uses less digits than its factorization.

21197079804 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19847549 (or 19847547 counting only the distinct ones).

The product of its (nonzero) digits is 254016, while the sum is 48.

The spelling of 21197079804 in words is "twenty-one billion, one hundred ninety-seven million, seventy-nine thousand, eight hundred four".