20880820 has 12 divisors (see below), whose sum is σ = 43849764. Its totient is φ = 8352320.

The previous prime is 20880809. The next prime is 20880833. The reversal of 20880820 is 2808802.

It can be written as a sum of positive squares in 2 ways, for example, as 16032016 + 4848804 = 4004^2 + 2202^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 522001 + ... + 522040.

It is an arithmetic number, because the mean of its divisors is an integer number (3654147).

Almost surely, 2^20880820 is an apocalyptic number.

20880820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20880820 is an abundant number, since it is smaller than the sum of its proper divisors (22968944).

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

20880820 is a wasteful number, since it uses less digits than its factorization.

20880820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1044050 (or 1044048 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 28.

The square root of 20880820 is about 4569.5535886999. The cubic root of 20880820 is about 275.3695087900.

The spelling of 20880820 in words is "twenty million, eight hundred eighty thousand, eight hundred twenty".