667917 has 12 divisors (see below), whose sum is σ = 985920. Its totient is φ = 435528.

The previous prime is 667903. The next prime is 667921. The reversal of 667917 is 719766.

It is not a de Polignac number, because 667917 - 2¹² = 663821 is a prime.

It is a super-2 number, since 2×667917² = 892226237778, which contains 22 as substring.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

667917 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667987) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 367 + ... + 1212.

It is an arithmetic number, because the mean of its divisors is an integer number (82160).

2⁶⁶⁷⁹¹⁷ is an apocalyptic number.

It is an amenable number.

667917 is a deficient number, since it is larger than the sum of its proper divisors (318003).

667917 is a wasteful number, since it uses less digits than its factorization.

667917 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1632 (or 1629 counting only the distinct ones).

The product of its digits is 15876, while the sum is 36.

The square root of 667917 is about 817.2618919294. The cubic root of 667917 is about 87.4126257054.

The spelling of 667917 in words is "six hundred sixty-seven thousand, nine hundred seventeen".