666733340731 has 2 divisors, whose sum is σ = 666733340732. Its totient is φ = 666733340730.

The previous prime is 666733340729. The next prime is 666733340753. The reversal of 666733340731 is 137043337666.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 666733340731 - 2¹ = 666733340729 is a prime.

It is a super-2 number, since 2×666733340731² (a number of 24 digits) contains 22 as substring.

Together with 666733340729, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (666733340761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333366670365 + 333366670366.

It is an arithmetic number, because the mean of its divisors is an integer number (333366670366).

Almost surely, 2^666733340731 is an apocalyptic number.

666733340731 is a deficient number, since it is larger than the sum of its proper divisors (1).

666733340731 is an equidigital number, since it uses as much as digits as its factorization.

666733340731 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3429216, while the sum is 49.

The spelling of 666733340731 in words is "six hundred sixty-six billion, seven hundred thirty-three million, three hundred forty thousand, seven hundred thirty-one".