15915 has 8 divisors (see below), whose sum is σ = 25488. Its totient is φ = 8480.

The previous prime is 15913. The next prime is 15919. The reversal of 15915 is 51951.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 15915 - 2¹ = 15913 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 15891 and 15900.

It is not an unprimeable number, because it can be changed into a prime (15913) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 516 + ... + 545.

It is an arithmetic number, because the mean of its divisors is an integer number (3186).

2¹⁵⁹¹⁵ is an apocalyptic number.

15915 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

15915 is a deficient number, since it is larger than the sum of its proper divisors (9573).

15915 is a wasteful number, since it uses less digits than its factorization.

15915 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1069.

The product of its digits is 225, while the sum is 21.

The square root of 15915 is about 126.1546669767. The cubic root of 15915 is about 25.1537195415.

It can be divided in two parts, 1591 and 5, that added together give a triangular number (1596 = T₅₆).

The spelling of 15915 in words is "fifteen thousand, nine hundred fifteen".