20908920 has 32 divisors (see below), whose sum is σ = 62727120. Its totient is φ = 5575680.

The previous prime is 20908907. The next prime is 20908931. The reversal of 20908920 is 2980902.

It is a Harshad number since it is a multiple of its sum of digits (30).

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, 87001 + ... + 87240.

Almost surely, 2^20908920 is an apocalyptic number.

20908920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20908920 is an abundant number, since it is smaller than the sum of its proper divisors (41818200).

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

20908920 is a wasteful number, since it uses less digits than its factorization.

20908920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 174255 (or 174251 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 30.

The square root of 20908920 is about 4572.6272535600. The cubic root of 20908920 is about 275.4929779952.

The spelling of 20908920 in words is "twenty million, nine hundred eight thousand, nine hundred twenty".