25644431 has 2 divisors, whose sum is σ = 25644432. Its totient is φ = 25644430.

The previous prime is 25644407. The next prime is 25644467. The reversal of 25644431 is 13444652.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25644431 is a prime.

It is a super-2 number, since 2×25644431² = 1315273682627522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 25644394 and 25644403.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25644401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12822215 + 12822216.

It is an arithmetic number, because the mean of its divisors is an integer number (12822216).

Almost surely, 2^25644431 is an apocalyptic number.

25644431 is a deficient number, since it is larger than the sum of its proper divisors (1).

25644431 is an equidigital number, since it uses as much as digits as its factorization.

25644431 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11520, while the sum is 29.

The square root of 25644431 is about 5064.0330765113. The cubic root of 25644431 is about 294.8929267643.

The spelling of 25644431 in words is "twenty-five million, six hundred forty-four thousand, four hundred thirty-one".