21979196 has 12 divisors (see below), whose sum is σ = 38817240. Its totient is φ = 10888560.

The previous prime is 21979189. The next prime is 21979213. The reversal of 21979196 is 69197912.

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, 24770 + ... + 25641.

It is an arithmetic number, because the mean of its divisors is an integer number (3234770).

Almost surely, 2^21979196 is an apocalyptic number.

It is an amenable number.

21979196 is a deficient number, since it is larger than the sum of its proper divisors (16838044).

21979196 is a wasteful number, since it uses less digits than its factorization.

21979196 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50524 (or 50522 counting only the distinct ones).

The product of its digits is 61236, while the sum is 44.

The square root of 21979196 is about 4688.1975214361. The cubic root of 21979196 is about 280.1155815341.

The spelling of 21979196 in words is "twenty-one million, nine hundred seventy-nine thousand, one hundred ninety-six".