666731401177 has 2 divisors, whose sum is σ = 666731401178. Its totient is φ = 666731401176.

The previous prime is 666731401139. The next prime is 666731401229. The reversal of 666731401177 is 771104137666.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 404033124496 + 262698276681 = 635636^2 + 512541^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-666731401177 is a prime.

It is a super-2 number, since 2×666731401177² (a number of 24 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 666731401177.

It is not a weakly prime, because it can be changed into another prime (666732401177) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333365700588 + 333365700589.

It is an arithmetic number, because the mean of its divisors is an integer number (333365700589).

Almost surely, 2^666731401177 is an apocalyptic number.

It is an amenable number.

666731401177 is a deficient number, since it is larger than the sum of its proper divisors (1).

666731401177 is an equidigital number, since it uses as much as digits as its factorization.

666731401177 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 889056, while the sum is 49.

The spelling of 666731401177 in words is "six hundred sixty-six billion, seven hundred thirty-one million, four hundred one thousand, one hundred seventy-seven".