20508820 has 24 divisors (see below), whose sum is σ = 43360128. Its totient is φ = 8148000.

The previous prime is 20508811. The next prime is 20508833. The reversal of 20508820 is 2880502.

It is a super-2 number, since 2×20508820² = 841223395584800, which contains 22 as substring.

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, 376 + ... + 6415.

It is an arithmetic number, because the mean of its divisors is an integer number (1806672).

Almost surely, 2^20508820 is an apocalyptic number.

20508820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20508820 is an abundant number, since it is smaller than the sum of its proper divisors (22851308).

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

20508820 is a wasteful number, since it uses less digits than its factorization.

20508820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6951 (or 6949 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 25.

The square root of 20508820 is about 4528.6664703862. Note that the first 3 decimals coincide. The cubic root of 20508820 is about 273.7244285727.

The spelling of 20508820 in words is "twenty million, five hundred eight thousand, eight hundred twenty".