666431066 has 12 divisors (see below), whose sum is σ = 1162854378. Its totient is φ = 285613272.

The previous prime is 666431047. The next prime is 666431081. The reversal of 666431066 is 660134666.

It can be written as a sum of positive squares in only one way, i.e., 601966225 + 64464841 = 24535^2 + 8029^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3400061 + ... + 3400256.

Almost surely, 2^666431066 is an apocalyptic number.

666431066 is a deficient number, since it is larger than the sum of its proper divisors (496423312).

666431066 is a wasteful number, since it uses less digits than its factorization.

666431066 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6800333 (or 6800326 counting only the distinct ones).

The product of its (nonzero) digits is 93312, while the sum is 38.

The square root of 666431066 is about 25815.3261842650. The cubic root of 666431066 is about 873.4775445414.

The spelling of 666431066 in words is "six hundred sixty-six million, four hundred thirty-one thousand, sixty-six".