666666736 has 10 divisors (see below), whose sum is σ = 1291666832. Its totient is φ = 333333360.

The previous prime is 666666727. The next prime is 666666757. The reversal of 666666736 is 637666666.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20833320 + ... + 20833351.

Almost surely, 2^666666736 is an apocalyptic number.

It is an amenable number.

666666736 is a deficient number, since it is larger than the sum of its proper divisors (625000096).

666666736 is a wasteful number, since it uses less digits than its factorization.

666666736 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41666679 (or 41666673 counting only the distinct ones).

The product of its digits is 5878656, while the sum is 52.

The square root of 666666736 is about 25819.8903173503. The cubic root of 666666736 is about 873.5804950204.

The spelling of 666666736 in words is "six hundred sixty-six million, six hundred sixty-six thousand, seven hundred thirty-six".