20508907 has 2 divisors, whose sum is σ = 20508908. Its totient is φ = 20508906.

The previous prime is 20508899. The next prime is 20508911. The reversal of 20508907 is 70980502.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20508907 - 2³ = 20508899 is a prime.

It is not a weakly prime, because it can be changed into another prime (20508937) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10254453 + 10254454.

It is an arithmetic number, because the mean of its divisors is an integer number (10254454).

Almost surely, 2^20508907 is an apocalyptic number.

20508907 is a deficient number, since it is larger than the sum of its proper divisors (1).

20508907 is an equidigital number, since it uses as much as digits as its factorization.

20508907 is an evil number, because the sum of its binary digits is even.

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

The square root of 20508907 is about 4528.6760758526. The cubic root of 20508907 is about 273.7248156255.

The spelling of 20508907 in words is "twenty million, five hundred eight thousand, nine hundred seven".