20804512 has 36 divisors (see below), whose sum is σ = 42851970. Its totient is φ = 9941888.

The previous prime is 20804501. The next prime is 20804527. The reversal of 20804512 is 21540802.

It can be written as a sum of positive squares in only one way, i.e., 11587216 + 9217296 = 3404^2 + 3036^2 .

It is an unprimeable number.

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, 16314 + ... + 17542.

Almost surely, 2^20804512 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20804512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21425985).

20804512 is an abundant number, since it is smaller than the sum of its proper divisors (22047458).

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

20804512 is a wasteful number, since it uses less digits than its factorization.

20804512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1285 (or 1254 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 22.

The square root of 20804512 is about 4561.1963342965. The cubic root of 20804512 is about 275.0336575884.

It can be divided in two parts, 20804 and 512, that added together give a square (21316 = 146²).

The spelling of 20804512 in words is "twenty million, eight hundred four thousand, five hundred twelve".