25138581 has 24 divisors (see below), whose sum is σ = 36629280. Its totient is φ = 15327936.

The previous prime is 25138573. The next prime is 25138583. The reversal of 25138581 is 18583152.

It is a happy number.

It is not a de Polignac number, because 25138581 - 2³ = 25138573 is a prime.

It is a super-2 number, since 2×25138581² = 1263896509387122, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25138583) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 90615 + ... + 90891.

It is an arithmetic number, because the mean of its divisors is an integer number (1526220).

Almost surely, 2^25138581 is an apocalyptic number.

It is an amenable number.

25138581 is a deficient number, since it is larger than the sum of its proper divisors (11490699).

25138581 is a wasteful number, since it uses less digits than its factorization.

25138581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 485 (or 472 counting only the distinct ones).

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

The square root of 25138581 is about 5013.8389483509. The cubic root of 25138581 is about 292.9410629785.

The spelling of 25138581 in words is "twenty-five million, one hundred thirty-eight thousand, five hundred eighty-one".