20626909 has 2 divisors, whose sum is σ = 20626910. Its totient is φ = 20626908.

The previous prime is 20626897. The next prime is 20626919. The reversal of 20626909 is 90962602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18301284 + 2325625 = 4278^2 + 1525^2 .

It is a cyclic number.

It is not a de Polignac number, because 20626909 - 2⁵ = 20626877 is a prime.

It is a plaindrome in base 16.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20626919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10313454 + 10313455.

It is an arithmetic number, because the mean of its divisors is an integer number (10313455).

Almost surely, 2^20626909 is an apocalyptic number.

It is an amenable number.

20626909 is a deficient number, since it is larger than the sum of its proper divisors (1).

20626909 is an equidigital number, since it uses as much as digits as its factorization.

20626909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11664, while the sum is 34.

The square root of 20626909 is about 4541.6857002659. The cubic root of 20626909 is about 274.2487883672.

The spelling of 20626909 in words is "twenty million, six hundred twenty-six thousand, nine hundred nine".