667984 has 20 divisors (see below), whose sum is σ = 1312416. Its totient is φ = 329312.

The previous prime is 667963. The next prime is 667987. The reversal of 667984 is 489766.

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 pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1077 + ... + 1579.

2⁶⁶⁷⁹⁸⁴ is an apocalyptic number.

It is an amenable number.

667984 is a deficient number, since it is larger than the sum of its proper divisors (644432).

667984 is a wasteful number, since it uses less digits than its factorization.

667984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 594 (or 588 counting only the distinct ones).

The product of its digits is 72576, while the sum is 40.

The square root of 667984 is about 817.3028814338. The cubic root of 667984 is about 87.4155484489.

The spelling of 667984 in words is "six hundred sixty-seven thousand, nine hundred eighty-four".