25989917 has 2 divisors, whose sum is σ = 25989918. Its totient is φ = 25989916.

The previous prime is 25989883. The next prime is 25989949. The reversal of 25989917 is 71998952.

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., 18267076 + 7722841 = 4274^2 + 2779^2 .

It is a cyclic number.

It is not a de Polignac number, because 25989917 - 2²⁰ = 24941341 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25989217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12994958 + 12994959.

It is an arithmetic number, because the mean of its divisors is an integer number (12994959).

Almost surely, 2^25989917 is an apocalyptic number.

It is an amenable number.

25989917 is a deficient number, since it is larger than the sum of its proper divisors (1).

25989917 is an equidigital number, since it uses as much as digits as its factorization.

25989917 is an evil number, because the sum of its binary digits is even.

The product of its digits is 408240, while the sum is 50.

The square root of 25989917 is about 5098.0306982206. The cubic root of 25989917 is about 296.2113059304.

The spelling of 25989917 in words is "twenty-five million, nine hundred eighty-nine thousand, nine hundred seventeen".