666266631 has 8 divisors (see below), whose sum is σ = 888491520. Its totient is φ = 444109752.

The previous prime is 666266609. The next prime is 666266651. The reversal of 666266631 is 136662666.

It is a happy number.

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

It is a de Polignac number, because none of the positive numbers 2^k-666266631 is a prime.

It is a super-2 number, since 2×666266631² = 887822447168180322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666266651) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13866 + ... + 39048.

It is an arithmetic number, because the mean of its divisors is an integer number (111061440).

Almost surely, 2^666266631 is an apocalyptic number.

666266631 is a deficient number, since it is larger than the sum of its proper divisors (222224889).

666266631 is a wasteful number, since it uses less digits than its factorization.

666266631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34005.

The product of its digits is 279936, while the sum is 42.

The square root of 666266631 is about 25812.1411548907. The cubic root of 666266631 is about 873.4056981034.

The spelling of 666266631 in words is "six hundred sixty-six million, two hundred sixty-six thousand, six hundred thirty-one".