20508972 has 24 divisors (see below), whose sum is σ = 52204992. Its totient is φ = 6214800.

The previous prime is 20508941. The next prime is 20508991. The reversal of 20508972 is 27980502.

It is a Harshad number since it is a multiple of its sum of digits (33).

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, 77554 + ... + 77817.

It is an arithmetic number, because the mean of its divisors is an integer number (2175208).

Almost surely, 2^20508972 is an apocalyptic number.

20508972 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

20508972 is an abundant number, since it is smaller than the sum of its proper divisors (31696020).

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

20508972 is a wasteful number, since it uses less digits than its factorization.

20508972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155389 (or 155387 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 33.

The square root of 20508972 is about 4528.6832523373. The cubic root of 20508972 is about 273.7251048022.

The spelling of 20508972 in words is "twenty million, five hundred eight thousand, nine hundred seventy-two".