15813 has 12 divisors (see below), whose sum is σ = 26208. Its totient is φ = 9000.

The previous prime is 15809. The next prime is 15817. The reversal of 15813 is 31851.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (15809) and next prime (15817).

It is not a de Polignac number, because 15813 - 2² = 15809 is a prime.

It is a hoax number, since the sum of its digits (18) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15817) 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, 63 + ... + 188.

It is an arithmetic number, because the mean of its divisors is an integer number (2184).

2¹⁵⁸¹³ is an apocalyptic number.

It is an amenable number.

15813 is a deficient number, since it is larger than the sum of its proper divisors (10395).

15813 is a wasteful number, since it uses less digits than its factorization.

15813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 264 (or 261 counting only the distinct ones).

The product of its digits is 120, while the sum is 18.

The square root of 15813 is about 125.7497514908. The cubic root of 15813 is about 25.0998671972.

It can be divided in two parts, 158 and 13, that added together give a palindrome (171).

The spelling of 15813 in words is "fifteen thousand, eight hundred thirteen".