25881531 has 32 divisors (see below), whose sum is σ = 39836160. Its totient is φ = 14805504.

The previous prime is 25881523. The next prime is 25881533. The reversal of 25881531 is 13518852.

It is a happy number.

It is not a de Polignac number, because 25881531 - 2³ = 25881523 is a prime.

It is a super-2 number, since 2×25881531² = 1339707293807922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 25881492 and 25881501.

It is not an unprimeable number, because it can be changed into a prime (25881533) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 68100 + ... + 68478.

It is an arithmetic number, because the mean of its divisors is an integer number (1244880).

Almost surely, 2^25881531 is an apocalyptic number.

25881531 is a deficient number, since it is larger than the sum of its proper divisors (13954629).

25881531 is a wasteful number, since it uses less digits than its factorization.

25881531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 515.

The product of its digits is 9600, while the sum is 33.

The square root of 25881531 is about 5087.3894091174. The cubic root of 25881531 is about 295.7989679228.

The spelling of 25881531 in words is "twenty-five million, eight hundred eighty-one thousand, five hundred thirty-one".