20920920 has 64 divisors (see below), whose sum is σ = 63076320. Its totient is φ = 5551104.

The previous prime is 20920909. The next prime is 20920927. The reversal of 20920920 is 2902902.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20920927) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 37282 + ... + 37838.

Almost surely, 2^20920920 is an apocalyptic number.

20920920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20920920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31538160).

20920920 is an abundant number, since it is smaller than the sum of its proper divisors (42155400).

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

20920920 is a wasteful number, since it uses less digits than its factorization.

20920920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 884 (or 880 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 24.

The square root of 20920920 is about 4573.9392212840. The cubic root of 20920920 is about 275.5456713512.

The spelling of 20920920 in words is "twenty million, nine hundred twenty thousand, nine hundred twenty".