25531613 has 4 divisors (see below), whose sum is σ = 25542108. Its totient is φ = 25521120.

The previous prime is 25531607. The next prime is 25531619. The reversal of 25531613 is 31613552.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is an interprime number because it is at equal distance from previous prime (25531607) and next prime (25531619).

It can be written as a sum of positive squares in 2 ways, for example, as 15784729 + 9746884 = 3973^2 + 3122^2 .

It is a cyclic number.

It is not a de Polignac number, because 25531613 - 2⁶ = 25531549 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25531619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 503 + ... + 7163.

It is an arithmetic number, because the mean of its divisors is an integer number (6385527).

Almost surely, 2^25531613 is an apocalyptic number.

It is an amenable number.

25531613 is a deficient number, since it is larger than the sum of its proper divisors (10495).

25531613 is an equidigital number, since it uses as much as digits as its factorization.

25531613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10494.

The product of its digits is 2700, while the sum is 26.

The square root of 25531613 is about 5052.8816530768. The cubic root of 25531613 is about 294.4598484986.

The spelling of 25531613 in words is "twenty-five million, five hundred thirty-one thousand, six hundred thirteen".