20992724 has 6 divisors (see below), whose sum is σ = 36737274. Its totient is φ = 10496360.

The previous prime is 20992711. The next prime is 20992747. The reversal of 20992724 is 42729902.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 18490000 + 2502724 = 4300^2 + 1582^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2624087 + ... + 2624094.

It is an arithmetic number, because the mean of its divisors is an integer number (6122879).

Almost surely, 2^20992724 is an apocalyptic number.

It is an amenable number.

20992724 is a deficient number, since it is larger than the sum of its proper divisors (15744550).

20992724 is a wasteful number, since it uses less digits than its factorization.

20992724 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5248185 (or 5248183 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 35.

The square root of 20992724 is about 4581.7817494944. The cubic root of 20992724 is about 275.8605505728.

The spelling of 20992724 in words is "twenty million, nine hundred ninety-two thousand, seven hundred twenty-four".