25641531 has 12 divisors (see below), whose sum is σ = 37173240. Its totient is φ = 17031840.

The previous prime is 25641529. The next prime is 25641563. The reversal of 25641531 is 13514652.

It is not a de Polignac number, because 25641531 - 2¹ = 25641529 is a prime.

It is a super-2 number, since 2×25641531² = 1314976224047922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 25641495 and 25641504.

It is not an unprimeable number, because it can be changed into a prime (25641521) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2541 + ... + 7598.

It is an arithmetic number, because the mean of its divisors is an integer number (3097770).

Almost surely, 2^25641531 is an apocalyptic number.

25641531 is a deficient number, since it is larger than the sum of its proper divisors (11531709).

25641531 is a wasteful number, since it uses less digits than its factorization.

25641531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10426 (or 10423 counting only the distinct ones).

The product of its digits is 3600, while the sum is 27.

The square root of 25641531 is about 5063.7467353729. The cubic root of 25641531 is about 294.8818103582.

It can be divided in two parts, 2564 and 1531, that added together give a triangular number (4095 = T₉₀).

The spelling of 25641531 in words is "twenty-five million, six hundred forty-one thousand, five hundred thirty-one".