25391969 has 2 divisors, whose sum is σ = 25391970. Its totient is φ = 25391968.

The previous prime is 25391963. The next prime is 25392041. The reversal of 25391969 is 96919352.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24137569 + 1254400 = 4913^2 + 1120^2 .

It is a cyclic number.

It is not a de Polignac number, because 25391969 - 2⁸ = 25391713 is a prime.

It is a super-2 number, since 2×25391969² = 1289504179393922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (25391963) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12695984 + 12695985.

It is an arithmetic number, because the mean of its divisors is an integer number (12695985).

Almost surely, 2^25391969 is an apocalyptic number.

It is an amenable number.

25391969 is a deficient number, since it is larger than the sum of its proper divisors (1).

25391969 is an equidigital number, since it uses as much as digits as its factorization.

25391969 is an evil number, because the sum of its binary digits is even.

The product of its digits is 131220, while the sum is 44.

The square root of 25391969 is about 5039.0444530685. The cubic root of 25391969 is about 293.9220218327.

The spelling of 25391969 in words is "twenty-five million, three hundred ninety-one thousand, nine hundred sixty-nine".