20872820 has 24 divisors (see below), whose sum is σ = 43943424. Its totient is φ = 8328096.

The previous prime is 20872807. The next prime is 20872853. The reversal of 20872820 is 2827802.

It is a super-2 number, since 2×20872820² = 871349229504800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8669 + ... + 10811.

It is an arithmetic number, because the mean of its divisors is an integer number (1830976).

Almost surely, 2^20872820 is an apocalyptic number.

20872820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20872820 is an abundant number, since it is smaller than the sum of its proper divisors (23070604).

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

20872820 is a wasteful number, since it uses less digits than its factorization.

20872820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2639 (or 2637 counting only the distinct ones).

The product of its (nonzero) digits is 3584, while the sum is 29.

The square root of 20872820 is about 4568.6781458098. The cubic root of 20872820 is about 275.3343371593.

The spelling of 20872820 in words is "twenty million, eight hundred seventy-two thousand, eight hundred twenty".