25518225631 has 2 divisors, whose sum is σ = 25518225632. Its totient is φ = 25518225630.

The previous prime is 25518225619. The next prime is 25518225647. The reversal of 25518225631 is 13652281552.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 25518225631 - 2⁷ = 25518225503 is a prime.

It is a super-2 number, since 2×25518225631² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25518225611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12759112815 + 12759112816.

It is an arithmetic number, because the mean of its divisors is an integer number (12759112816).

Almost surely, 2^25518225631 is an apocalyptic number.

25518225631 is a deficient number, since it is larger than the sum of its proper divisors (1).

25518225631 is an equidigital number, since it uses as much as digits as its factorization.

25518225631 is an evil number, because the sum of its binary digits is even.

The product of its digits is 144000, while the sum is 40.

The spelling of 25518225631 in words is "twenty-five billion, five hundred eighteen million, two hundred twenty-five thousand, six hundred thirty-one".