666293647 has 8 divisors (see below), whose sum is σ = 719238240. Its totient is φ = 615347040.

The previous prime is 666293629. The next prime is 666293671. The reversal of 666293647 is 746392666.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 666293647 - 2⁷ = 666293519 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 666293647.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666296647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 498804 + ... + 500137.

It is an arithmetic number, because the mean of its divisors is an integer number (89904780).

Almost surely, 2^666293647 is an apocalyptic number.

666293647 is a deficient number, since it is larger than the sum of its proper divisors (52944593).

666293647 is a wasteful number, since it uses less digits than its factorization.

666293647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 998993.

The product of its digits is 1959552, while the sum is 49.

The square root of 666293647 is about 25812.6644692097. The cubic root of 666293647 is about 873.4175029917.

The spelling of 666293647 in words is "six hundred sixty-six million, two hundred ninety-three thousand, six hundred forty-seven".