667977 has 4 divisors (see below), whose sum is σ = 890640. Its totient is φ = 445316.

The previous prime is 667963. The next prime is 667987. The reversal of 667977 is 779766.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 667977 - 2¹² = 663881 is a prime.

It is a D-number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 667977.

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 3 ways as a sum of consecutive naturals, for example, 111327 + ... + 111332.

It is an arithmetic number, because the mean of its divisors is an integer number (222660).

2⁶⁶⁷⁹⁷⁷ is an apocalyptic number.

It is an amenable number.

667977 is a deficient number, since it is larger than the sum of its proper divisors (222663).

667977 is a wasteful number, since it uses less digits than its factorization.

667977 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 222662.

The product of its digits is 111132, while the sum is 42.

The square root of 667977 is about 817.2985990444. The cubic root of 667977 is about 87.4152430968.

The spelling of 667977 in words is "six hundred sixty-seven thousand, nine hundred seventy-seven".