15779 has 4 divisors (see below), whose sum is σ = 16320. Its totient is φ = 15240.

The previous prime is 15773. The next prime is 15787. The reversal of 15779 is 97751.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 97751 = 239 ⋅409.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15779 is a prime.

It is a Duffinian number.

It is a plaindrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (15773) 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, 224 + ... + 285.

It is an arithmetic number, because the mean of its divisors is an integer number (4080).

2¹⁵⁷⁷⁹ is an apocalyptic number.

15779 is a deficient number, since it is larger than the sum of its proper divisors (541).

15779 is an equidigital number, since it uses as much as digits as its factorization.

15779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 540.

The product of its digits is 2205, while the sum is 29.

The square root of 15779 is about 125.6144896101. The cubic root of 15779 is about 25.0818649658.

It can be divided in two parts, 157 and 79, that multiplied together give a triangular number (12403 = T₁₅₇).

The spelling of 15779 in words is "fifteen thousand, seven hundred seventy-nine".