20905708 has 12 divisors (see below), whose sum is σ = 37026360. Its totient is φ = 10326752.

The previous prime is 20905679. The next prime is 20905711. The reversal of 20905708 is 80750902.

It is a self number, because there is not a number n which added to its sum of digits gives 20905708.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31153 + ... + 31816.

It is an arithmetic number, because the mean of its divisors is an integer number (3085530).

Almost surely, 2^20905708 is an apocalyptic number.

It is an amenable number.

20905708 is a deficient number, since it is larger than the sum of its proper divisors (16120652).

20905708 is a wasteful number, since it uses less digits than its factorization.

20905708 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63056 (or 63054 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 31.

The square root of 20905708 is about 4572.2760196646. The cubic root of 20905708 is about 275.4788703200.

The spelling of 20905708 in words is "twenty million, nine hundred five thousand, seven hundred eight".