667956679 has 8 divisors (see below), whose sum is σ = 719589920. Its totient is φ = 616359456.

The previous prime is 667956661. The next prime is 667956683. The reversal of 667956679 is 976659766.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 667956679 - 2⁷ = 667956551 is a prime.

It is a super-2 number, since 2×667956679² = 892332250041418082, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667956689) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39049 + ... + 53485.

It is an arithmetic number, because the mean of its divisors is an integer number (89948740).

Almost surely, 2^667956679 is an apocalyptic number.

667956679 is a deficient number, since it is larger than the sum of its proper divisors (51633241).

667956679 is a wasteful number, since it uses less digits than its factorization.

667956679 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18009.

The product of its digits is 25719120, while the sum is 61.

The square root of 667956679 is about 25844.8578831457. The cubic root of 667956679 is about 874.1435664751.

The spelling of 667956679 in words is "six hundred sixty-seven million, nine hundred fifty-six thousand, six hundred seventy-nine".