666776 has 16 divisors (see below), whose sum is σ = 1364040. Its totient is φ = 303040.

The previous prime is 666773. The next prime is 666811. The reversal of 666776 is 677666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666773) 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, 3701 + ... + 3876.

2⁶⁶⁶⁷⁷⁶ is an apocalyptic number.

It is an amenable number.

666776 is an abundant number, since it is smaller than the sum of its proper divisors (697264).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

666776 is a wasteful number, since it uses less digits than its factorization.

666776 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7594 (or 7590 counting only the distinct ones).

The product of its digits is 63504, while the sum is 38.

The square root of 666776 is about 816.5635309025. The cubic root of 666776 is about 87.3628217858.

The spelling of 666776 in words is "six hundred sixty-six thousand, seven hundred seventy-six".