20804900 has 18 divisors (see below), whose sum is σ = 45146850. Its totient is φ = 8321920.

The previous prime is 20804899. The next prime is 20804909. The reversal of 20804900 is 940802.

It can be written as a sum of positive squares in 3 ways, for example, as 6120676 + 14684224 = 2474^2 + 3832^2 .

It is a super-4 number, since 4×20804900⁴ (a number of 30 digits) contains 4444 as substring.

It is not an unprimeable number, because it can be changed into a prime (20804909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 103925 + ... + 104124.

Almost surely, 2^20804900 is an apocalyptic number.

20804900 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20804900 is an abundant number, since it is smaller than the sum of its proper divisors (24341950).

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

20804900 is a wasteful number, since it uses less digits than its factorization.

20804900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 208063 (or 208056 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 20804900 is about 4561.2388667992. The cubic root of 20804900 is about 275.0353673521.

The spelling of 20804900 in words is "twenty million, eight hundred four thousand, nine hundred".