120665 has 4 divisors (see below), whose sum is σ = 144804. Its totient is φ = 96528.

The previous prime is 120661. The next prime is 120671. The reversal of 120665 is 566021.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 566021 = 47 ⋅12043.

It can be written as a sum of positive squares in 2 ways, for example, as 48841 + 71824 = 221^2 + 268^2 .

It is a cyclic number.

It is not a de Polignac number, because 120665 - 2² = 120661 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 120665.

It is not an unprimeable number, because it can be changed into a prime (120661) 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 3 ways as a sum of consecutive naturals, for example, 12062 + ... + 12071.

It is an arithmetic number, because the mean of its divisors is an integer number (36201).

2¹²⁰⁶⁶⁵ is an apocalyptic number.

It is an amenable number.

120665 is a deficient number, since it is larger than the sum of its proper divisors (24139).

120665 is an equidigital number, since it uses as much as digits as its factorization.

120665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24138.

The product of its (nonzero) digits is 360, while the sum is 20.

The square root of 120665 is about 347.3686802232. The cubic root of 120665 is about 49.4151865322.

Adding to 120665 its reverse (566021), we get a palindrome (686686).

It can be divided in two parts, 120 and 665, that multiplied together give a triangular number (79800 = T₃₉₉).

The spelling of 120665 in words is "one hundred twenty thousand, six hundred sixty-five".