2665 has 8 divisors (see below), whose sum is σ = 3528. Its totient is φ = 1920.

The previous prime is 2663. The next prime is 2671. The reversal of 2665 is 5662.

2665 = 36² + 37².

2665 is nontrivially palindromic in base 12.

2665 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 64 + 2601 = 8^2 + 51^2 .

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

It is not a de Polignac number, because 2665 - 2¹ = 2663 is a prime.

It is a Duffinian number.

2665 is an undulating number in base 8.

It is a nialpdrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (2663) 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, 45 + ... + 85.

It is an arithmetic number, because the mean of its divisors is an integer number (441).

2²⁶⁶⁵ is an apocalyptic number.

2665 is the 37-th centered square number.

It is an amenable number.

2665 is a deficient number, since it is larger than the sum of its proper divisors (863).

2665 is a wasteful number, since it uses less digits than its factorization.

2665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59.

The product of its digits is 360, while the sum is 19.

The square root of 2665 is about 51.6236379966. The cubic root of 2665 is about 13.8643358796.

Adding to 2665 its product of digits (360), we get a square (3025 = 55²).

It can be divided in two parts, 26 and 65, that added together give a triangular number (91 = T₁₃).

The spelling of 2665 in words is "two thousand, six hundred sixty-five".