20908666 has 12 divisors (see below), whose sum is σ = 31650318. Its totient is φ = 10359392.

The previous prime is 20908651. The next prime is 20908669. The reversal of 20908666 is 66680902.

It can be written as a sum of positive squares in 3 ways, for example, as 15249025 + 5659641 = 3905^2 + 2379^2 .

It is not an unprimeable number, because it can be changed into a prime (20908669) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 37260 + ... + 37816.

Almost surely, 2^20908666 is an apocalyptic number.

20908666 is a deficient number, since it is larger than the sum of its proper divisors (10741652).

20908666 is an equidigital number, since it uses as much as digits as its factorization.

20908666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 833 (or 696 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 37.

The square root of 20908666 is about 4572.5994795083. The cubic root of 20908666 is about 275.4918624347.

The spelling of 20908666 in words is "twenty million, nine hundred eight thousand, six hundred sixty-six".