20809792 has 14 divisors (see below), whose sum is σ = 41294558. Its totient is φ = 10404864.

The previous prime is 20809783. The next prime is 20809793. The reversal of 20809792 is 29790802.

It can be written as a sum of positive squares in only one way, i.e., 19501056 + 1308736 = 4416^2 + 1144^2 .

It is not an unprimeable number, because it can be changed into a prime (20809793) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 162513 + ... + 162640.

Almost surely, 2^20809792 is an apocalyptic number.

It is an amenable number.

20809792 is a deficient number, since it is larger than the sum of its proper divisors (20484766).

20809792 is an equidigital number, since it uses as much as digits as its factorization.

20809792 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 325165 (or 325155 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 37.

The square root of 20809792 is about 4561.7750930970. The cubic root of 20809792 is about 275.0569226519.

The spelling of 20809792 in words is "twenty million, eight hundred nine thousand, seven hundred ninety-two".