667768 has 8 divisors (see below), whose sum is σ = 1252080. Its totient is φ = 333880.

The previous prime is 667753. The next prime is 667769. The reversal of 667768 is 867766.

It is a tau number, because it is divible by the number of its divisors (8).

It is a self number, because there is not a number n which added to its sum of digits gives 667768.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667769) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41728 + ... + 41743.

It is an arithmetic number, because the mean of its divisors is an integer number (156510).

2⁶⁶⁷⁷⁶⁸ is an apocalyptic number.

It is an amenable number.

667768 is a deficient number, since it is larger than the sum of its proper divisors (584312).

667768 is a wasteful number, since it uses less digits than its factorization.

667768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83477 (or 83473 counting only the distinct ones).

The product of its digits is 84672, while the sum is 40.

The square root of 667768 is about 817.1707287954. The cubic root of 667768 is about 87.4061251723.

The spelling of 667768 in words is "six hundred sixty-seven thousand, seven hundred sixty-eight".