25431517 has 2 divisors, whose sum is σ = 25431518. Its totient is φ = 25431516.

The previous prime is 25431509. The next prime is 25431569. The reversal of 25431517 is 71513452.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20169081 + 5262436 = 4491^2 + 2294^2 .

It is a cyclic number.

It is not a de Polignac number, because 25431517 - 2³ = 25431509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25431577) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12715758 + 12715759.

It is an arithmetic number, because the mean of its divisors is an integer number (12715759).

Almost surely, 2^25431517 is an apocalyptic number.

It is an amenable number.

25431517 is a deficient number, since it is larger than the sum of its proper divisors (1).

25431517 is an equidigital number, since it uses as much as digits as its factorization.

25431517 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4200, while the sum is 28.

The square root of 25431517 is about 5042.9670829780. The cubic root of 25431517 is about 294.0745372274.

Adding to 25431517 its reverse (71513452), we get a palindrome (96944969).

The spelling of 25431517 in words is "twenty-five million, four hundred thirty-one thousand, five hundred seventeen".