20675917 has 2 divisors, whose sum is σ = 20675918. Its totient is φ = 20675916.

The previous prime is 20675813. The next prime is 20675923. The reversal of 20675917 is 71957602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20666116 + 9801 = 4546^2 + 99^2 .

It is a cyclic number.

It is not a de Polignac number, because 20675917 - 2⁷ = 20675789 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20675947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10337958 + 10337959.

It is an arithmetic number, because the mean of its divisors is an integer number (10337959).

Almost surely, 2^20675917 is an apocalyptic number.

It is an amenable number.

20675917 is a deficient number, since it is larger than the sum of its proper divisors (1).

20675917 is an equidigital number, since it uses as much as digits as its factorization.

20675917 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 26460, while the sum is 37.

The square root of 20675917 is about 4547.0778528633. The cubic root of 20675917 is about 274.4658148123.

The spelling of 20675917 in words is "twenty million, six hundred seventy-five thousand, nine hundred seventeen".