666666740731 has 2 divisors, whose sum is σ = 666666740732. Its totient is φ = 666666740730.

The previous prime is 666666740711. The next prime is 666666740767. The reversal of 666666740731 is 137047666666.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 666666740731 - 2²⁵ = 666633186299 is a prime.

It is a super-2 number, since 2×666666740731² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (666666740711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333333370365 + 333333370366.

It is an arithmetic number, because the mean of its divisors is an integer number (333333370366).

Almost surely, 2^666666740731 is an apocalyptic number.

666666740731 is a deficient number, since it is larger than the sum of its proper divisors (1).

666666740731 is an equidigital number, since it uses as much as digits as its factorization.

666666740731 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27433728, while the sum is 58.

The spelling of 666666740731 in words is "six hundred sixty-six billion, six hundred sixty-six million, seven hundred forty thousand, seven hundred thirty-one".