20399875 has 8 divisors (see below), whose sum is σ = 25459200. Its totient is φ = 16319800.

The previous prime is 20399867. The next prime is 20399887. The reversal of 20399875 is 57899302.

It is a happy number.

It is not a de Polignac number, because 20399875 - 2³ = 20399867 is a prime.

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, 81475 + ... + 81724.

It is an arithmetic number, because the mean of its divisors is an integer number (3182400).

Almost surely, 2^20399875 is an apocalyptic number.

20399875 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

20399875 is a deficient number, since it is larger than the sum of its proper divisors (5059325).

20399875 is an equidigital number, since it uses as much as digits as its factorization.

20399875 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163214 (or 163204 counting only the distinct ones).

The product of its (nonzero) digits is 136080, while the sum is 43.

The square root of 20399875 is about 4516.6220785007. The cubic root of 20399875 is about 273.2388835212.

The spelling of 20399875 in words is "twenty million, three hundred ninety-nine thousand, eight hundred seventy-five".