25679989 has 2 divisors, whose sum is σ = 25679990. Its totient is φ = 25679988.

The previous prime is 25679959. The next prime is 25679999. The reversal of 25679989 is 98997652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23444964 + 2235025 = 4842^2 + 1495^2 .

It is a cyclic number.

It is not a de Polignac number, because 25679989 - 2⁷ = 25679861 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25679959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12839994 + 12839995.

It is an arithmetic number, because the mean of its divisors is an integer number (12839995).

Almost surely, 2^25679989 is an apocalyptic number.

It is an amenable number.

25679989 is a deficient number, since it is larger than the sum of its proper divisors (1).

25679989 is an equidigital number, since it uses as much as digits as its factorization.

25679989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2449440, while the sum is 55.

The square root of 25679989 is about 5067.5426983894. The cubic root of 25679989 is about 295.0291611506.

The spelling of 25679989 in words is "twenty-five million, six hundred seventy-nine thousand, nine hundred eighty-nine".