20972686 has 12 divisors (see below), whose sum is σ = 36595368. Its totient is φ = 8988252.

The previous prime is 20972663. The next prime is 20972729. The reversal of 20972686 is 68627902.

It is a congruent number.

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 5 ways as a sum of consecutive naturals, for example, 106906 + ... + 107101.

It is an arithmetic number, because the mean of its divisors is an integer number (3049614).

Almost surely, 2^20972686 is an apocalyptic number.

20972686 is a deficient number, since it is larger than the sum of its proper divisors (15622682).

20972686 is a wasteful number, since it uses less digits than its factorization.

20972686 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214023 (or 214016 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 40.

The square root of 20972686 is about 4579.5945235359. The cubic root of 20972686 is about 275.7727510506.

The spelling of 20972686 in words is "twenty million, nine hundred seventy-two thousand, six hundred eighty-six".