15979 has 6 divisors (see below), whose sum is σ = 17420. Its totient is φ = 14616.

The previous prime is 15973. The next prime is 15991. The reversal of 15979 is 97951.

It is not a de Polignac number, because 15979 - 2³ = 15971 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 15979.

It is not an unprimeable number, because it can be changed into a prime (15971) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 537 + ... + 565.

2¹⁵⁹⁷⁹ is an apocalyptic number.

15979 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

15979 is a deficient number, since it is larger than the sum of its proper divisors (1441).

15979 is an equidigital number, since it uses as much as digits as its factorization.

15979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77 (or 48 counting only the distinct ones).

The product of its digits is 2835, while the sum is 31.

The square root of 15979 is about 126.4080693627. The cubic root of 15979 is about 25.1873918621.

It can be divided in two parts, 159 and 79, that multiplied together give a triangular number (12561 = T₁₅₈).

The spelling of 15979 in words is "fifteen thousand, nine hundred seventy-nine".