666446972 has 12 divisors (see below), whose sum is σ = 1166468520. Its totient is φ = 333170256.

The previous prime is 666446953. The next prime is 666446987. The reversal of 666446972 is 279644666.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 666446972.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32003 + ... + 48549.

It is an arithmetic number, because the mean of its divisors is an integer number (97205710).

Almost surely, 2^666446972 is an apocalyptic number.

It is an amenable number.

666446972 is a deficient number, since it is larger than the sum of its proper divisors (500021548).

666446972 is a wasteful number, since it uses less digits than its factorization.

666446972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26620 (or 26618 counting only the distinct ones).

The product of its digits is 2612736, while the sum is 50.

The square root of 666446972 is about 25815.6342552338. The cubic root of 666446972 is about 873.4844937089.

The spelling of 666446972 in words is "six hundred sixty-six million, four hundred forty-six thousand, nine hundred seventy-two".