25639967 has 2 divisors, whose sum is σ = 25639968. Its totient is φ = 25639966.

The previous prime is 25639937. The next prime is 25639979. The reversal of 25639967 is 76993652.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 25639967 - 2⁸ = 25639711 is a prime.

It is a super-2 number, since 2×25639967² = 1314815815522178, which contains 22 as substring.

It is a Chen prime.

It is a zygodrome in base 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25639907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12819983 + 12819984.

It is an arithmetic number, because the mean of its divisors is an integer number (12819984).

Almost surely, 2^25639967 is an apocalyptic number.

25639967 is a deficient number, since it is larger than the sum of its proper divisors (1).

25639967 is an equidigital number, since it uses as much as digits as its factorization.

25639967 is an evil number, because the sum of its binary digits is even.

The product of its digits is 612360, while the sum is 47.

The square root of 25639967 is about 5063.5923019137. The cubic root of 25639967 is about 294.8758148175.

The spelling of 25639967 in words is "twenty-five million, six hundred thirty-nine thousand, nine hundred sixty-seven".