20638875 has 32 divisors (see below), whose sum is σ = 35103744. Its totient is φ = 10764000.

The previous prime is 20638861. The next prime is 20638931. The reversal of 20638875 is 57883602.

It is not a de Polignac number, because 20638875 - 2⁶ = 20638811 is a prime.

It is a super-2 number, since 2×20638875² = 851926322531250, which contains 22 as substring.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 17040 + ... + 18210.

It is an arithmetic number, because the mean of its divisors is an integer number (1096992).

Almost surely, 2^20638875 is an apocalyptic number.

20638875 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

20638875 is a deficient number, since it is larger than the sum of its proper divisors (14464869).

20638875 is a wasteful number, since it uses less digits than its factorization.

20638875 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1236 (or 1226 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 39.

The square root of 20638875 is about 4543.0028615443. The cubic root of 20638875 is about 274.3018101526.

The spelling of 20638875 in words is "twenty million, six hundred thirty-eight thousand, eight hundred seventy-five".