667961 has 8 divisors (see below), whose sum is σ = 784320. Its totient is φ = 556848.

The previous prime is 667949. The next prime is 667963. The reversal of 667961 is 169766.

It is a happy number.

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 667961 - 2¹⁰ = 666937 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667963) 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, 1031 + ... + 1548.

It is an arithmetic number, because the mean of its divisors is an integer number (98040).

2⁶⁶⁷⁹⁶¹ is an apocalyptic number.

It is an amenable number.

667961 is a deficient number, since it is larger than the sum of its proper divisors (116359).

667961 is a wasteful number, since it uses less digits than its factorization.

667961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2623.

The product of its digits is 13608, while the sum is 35.

The square root of 667961 is about 817.2888106416. The cubic root of 667961 is about 87.4145451411.

The spelling of 667961 in words is "six hundred sixty-seven thousand, nine hundred sixty-one".