666550636 has 6 divisors (see below), whose sum is σ = 1166463620. Its totient is φ = 333275316.

The previous prime is 666550613. The next prime is 666550691. The reversal of 666550636 is 636055666.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 666550592 and 666550601.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83318826 + ... + 83318833.

Almost surely, 2^666550636 is an apocalyptic number.

It is an amenable number.

666550636 is a deficient number, since it is larger than the sum of its proper divisors (499912984).

666550636 is a wasteful number, since it uses less digits than its factorization.

666550636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166637663 (or 166637661 counting only the distinct ones).

The product of its (nonzero) digits is 583200, while the sum is 43.

The square root of 666550636 is about 25817.6419527423. The cubic root of 666550636 is about 873.5297807339.

The spelling of 666550636 in words is "six hundred sixty-six million, five hundred fifty thousand, six hundred thirty-six".