20831908 has 12 divisors (see below), whose sum is σ = 37000432. Its totient is φ = 10260360.

The previous prime is 20831903. The next prime is 20831911. The reversal of 20831908 is 80913802.

It is a self number, because there is not a number n which added to its sum of digits gives 20831908.

It is not an unprimeable number, because it can be changed into a prime (20831903) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38598 + ... + 39133.

Almost surely, 2^20831908 is an apocalyptic number.

It is an amenable number.

20831908 is a deficient number, since it is larger than the sum of its proper divisors (16168524).

20831908 is a wasteful number, since it uses less digits than its factorization.

20831908 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77802 (or 77800 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 31.

The square root of 20831908 is about 4564.1985057620. The cubic root of 20831908 is about 275.1543288021.

The spelling of 20831908 in words is "twenty million, eight hundred thirty-one thousand, nine hundred eight".