25231649 has 2 divisors, whose sum is σ = 25231650. Its totient is φ = 25231648.

The previous prime is 25231643. The next prime is 25231651. The reversal of 25231649 is 94613252.

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., 19140625 + 6091024 = 4375^2 + 2468^2 .

It is a cyclic number.

It is not a de Polignac number, because 25231649 - 2²⁰ = 24183073 is a prime.

It is a super-2 number, since 2×25231649² = 1273272222518402, which contains 22 as substring.

Together with 25231651, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (25231643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12615824 + 12615825.

It is an arithmetic number, because the mean of its divisors is an integer number (12615825).

Almost surely, 2^25231649 is an apocalyptic number.

It is an amenable number.

25231649 is a deficient number, since it is larger than the sum of its proper divisors (1).

25231649 is an equidigital number, since it uses as much as digits as its factorization.

25231649 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12960, while the sum is 32.

The square root of 25231649 is about 5023.1114859218. Note that the first 3 decimals coincide. The cubic root of 25231649 is about 293.3021263575.

The spelling of 25231649 in words is "twenty-five million, two hundred thirty-one thousand, six hundred forty-nine".