20626657 has 2 divisors, whose sum is σ = 20626658. Its totient is φ = 20626656.

The previous prime is 20626643. The next prime is 20626667. The reversal of 20626657 is 75662602.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13845841 + 6780816 = 3721^2 + 2604^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20626657 is a prime.

It is not a weakly prime, because it can be changed into another prime (20626637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10313328 + 10313329.

It is an arithmetic number, because the mean of its divisors is an integer number (10313329).

Almost surely, 2^20626657 is an apocalyptic number.

It is an amenable number.

20626657 is a deficient number, since it is larger than the sum of its proper divisors (1).

20626657 is an equidigital number, since it uses as much as digits as its factorization.

20626657 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 30240, while the sum is 34.

The square root of 20626657 is about 4541.6579571782. The cubic root of 20626657 is about 274.2476715255.

The spelling of 20626657 in words is "twenty million, six hundred twenty-six thousand, six hundred fifty-seven".