25813 has 4 divisors (see below), whose sum is σ = 26208. Its totient is φ = 25420.

The previous prime is 25801. The next prime is 25819. The reversal of 25813 is 31852.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 25813 - 2⁹ = 25301 is a prime.

It is a Duffinian number.

It is a plaindrome in base 15.

It is a nialpdrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25819) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 73 + ... + 238.

It is an arithmetic number, because the mean of its divisors is an integer number (6552).

2²⁵⁸¹³ is an apocalyptic number.

It is an amenable number.

25813 is a deficient number, since it is larger than the sum of its proper divisors (395).

25813 is an equidigital number, since it uses as much as digits as its factorization.

25813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 394.

The product of its digits is 240, while the sum is 19.

The square root of 25813 is about 160.6642461782. The cubic root of 25813 is about 29.5537657809.

It can be divided in two parts, 25 and 813, that added together give a palindrome (838).

The spelling of 25813 in words is "twenty-five thousand, eight hundred thirteen".