20908711 has 2 divisors, whose sum is σ = 20908712. Its totient is φ = 20908710.

The previous prime is 20908697. The next prime is 20908747. The reversal of 20908711 is 11780902.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20908711 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20908711.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20908751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10454355 + 10454356.

It is an arithmetic number, because the mean of its divisors is an integer number (10454356).

Almost surely, 2^20908711 is an apocalyptic number.

20908711 is a deficient number, since it is larger than the sum of its proper divisors (1).

20908711 is an equidigital number, since it uses as much as digits as its factorization.

20908711 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1008, while the sum is 28.

The square root of 20908711 is about 4572.6044001204. The cubic root of 20908711 is about 275.4920600740.

It can be divided in two parts, 2090 and 8711, that added together give a palindrome (10801).

The spelling of 20908711 in words is "twenty million, nine hundred eight thousand, seven hundred eleven".