20979916 has 12 divisors (see below), whose sum is σ = 36765232. Its totient is φ = 10475568.

The previous prime is 20979899. The next prime is 20979923. The reversal of 20979916 is 61997902.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 106 + ... + 6478.

Almost surely, 2^20979916 is an apocalyptic number.

It is an amenable number.

20979916 is a deficient number, since it is larger than the sum of its proper divisors (15785316).

20979916 is a wasteful number, since it uses less digits than its factorization.

20979916 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7200 (or 7198 counting only the distinct ones).

The product of its (nonzero) digits is 61236, while the sum is 43.

The square root of 20979916 is about 4580.3838267115. The cubic root of 20979916 is about 275.8044368334.

The spelling of 20979916 in words is "twenty million, nine hundred seventy-nine thousand, nine hundred sixteen".