15775 has 6 divisors (see below), whose sum is σ = 19592. Its totient is φ = 12600.

The previous prime is 15773. The next prime is 15787. The reversal of 15775 is 57751.

15775 is nontrivially palindromic in base 4.

It is not a de Polignac number, because 15775 - 2¹ = 15773 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25), and also a Moran number because the ratio is a prime number: 631 = 15775 / (1 + 5 + 7 + 7 + 5).

It is a Duffinian number.

It is a plaindrome in base 9.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15773) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 291 + ... + 340.

2¹⁵⁷⁷⁵ is an apocalyptic number.

15775 is a deficient number, since it is larger than the sum of its proper divisors (3817).

15775 is an equidigital number, since it uses as much as digits as its factorization.

15775 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 641 (or 636 counting only the distinct ones).

The product of its digits is 1225, while the sum is 25.

The square root of 15775 is about 125.5985668708. The cubic root of 15775 is about 25.0797453567.

It can be divided in two parts, 157 and 75, that added together give a palindrome (232).

The spelling of 15775 in words is "fifteen thousand, seven hundred seventy-five".