25231631 has 2 divisors, whose sum is σ = 25231632. Its totient is φ = 25231630.

The previous prime is 25231603. The next prime is 25231637. The reversal of 25231631 is 13613252.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25231631 is a prime.

It is a super-2 number, since 2×25231631² = 1273270405840322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 25231597 and 25231606.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25231637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12615815 + 12615816.

It is an arithmetic number, because the mean of its divisors is an integer number (12615816).

Almost surely, 2^25231631 is an apocalyptic number.

25231631 is a deficient number, since it is larger than the sum of its proper divisors (1).

25231631 is an equidigital number, since it uses as much as digits as its factorization.

25231631 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1080, while the sum is 23.

The square root of 25231631 is about 5023.1096942034. The cubic root of 25231631 is about 293.3020566113.

Adding to 25231631 its reverse (13613252), we get a palindrome (38844883).

The spelling of 25231631 in words is "twenty-five million, two hundred thirty-one thousand, six hundred thirty-one".