72665 has 4 divisors (see below), whose sum is σ = 87204. Its totient is φ = 58128.

The previous prime is 72661. The next prime is 72671. The reversal of 72665 is 56627.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56627 = 17 ⋅3331.

It can be written as a sum of positive squares in 2 ways, for example, as 33856 + 38809 = 184^2 + 197^2 .

It is a cyclic number.

It is not a de Polignac number, because 72665 - 2² = 72661 is a prime.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 72665.

It is not an unprimeable number, because it can be changed into a prime (72661) 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, 7262 + ... + 7271.

It is an arithmetic number, because the mean of its divisors is an integer number (21801).

2⁷²⁶⁶⁵ is an apocalyptic number.

It is an amenable number.

72665 is a deficient number, since it is larger than the sum of its proper divisors (14539).

72665 is a wasteful number, since it uses less digits than its factorization.

72665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14538.

The product of its digits is 2520, while the sum is 26.

The square root of 72665 is about 269.5644635333. The cubic root of 72665 is about 41.7293633894.

It can be divided in two parts, 72 and 665, that added together give a palindrome (737).

The spelling of 72665 in words is "seventy-two thousand, six hundred sixty-five".