20816320 has 56 divisors (see below), whose sum is σ = 56656224. Its totient is φ = 7136256.

The previous prime is 20816309. The next prime is 20816359. The reversal of 20816320 is 2361802.

It is a tau number, because it is divible by the number of its divisors (56).

It is a junction number, because it is equal to n+sod(n) for n = 20816291 and 20816300.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2407 + ... + 6886.

Almost surely, 2^20816320 is an apocalyptic number.

20816320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20816320 is an abundant number, since it is smaller than the sum of its proper divisors (35839904).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20816320 is an equidigital number, since it uses as much as digits as its factorization.

20816320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9317 (or 9307 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 22.

The square root of 20816320 is about 4562.4905479354. The cubic root of 20816320 is about 275.0856812906.

The spelling of 20816320 in words is "twenty million, eight hundred sixteen thousand, three hundred twenty".