666965 has 16 divisors (see below), whose sum is σ = 892416. Its totient is φ = 475200.

The previous prime is 666959. The next prime is 666979. The reversal of 666965 is 569666.

666965 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 666965 - 2⁶ = 666901 is a prime.

It is a super-2 number, since 2×666965² = 889684622450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1850 + ... + 2180.

It is an arithmetic number, because the mean of its divisors is an integer number (55776).

2⁶⁶⁶⁹⁶⁵ is an apocalyptic number.

666965 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

666965 is a deficient number, since it is larger than the sum of its proper divisors (225451).

666965 is a wasteful number, since it uses less digits than its factorization.

666965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 380.

The product of its digits is 58320, while the sum is 38.

The square root of 666965 is about 816.6792516037. The cubic root of 666965 is about 87.3710754389.

The spelling of 666965 in words is "six hundred sixty-six thousand, nine hundred sixty-five".