666791817733 has 2 divisors, whose sum is σ = 666791817734. Its totient is φ = 666791817732.

The previous prime is 666791817709. The next prime is 666791817793. The reversal of 666791817733 is 337718197666.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 663610632129 + 3181185604 = 814623^2 + 56402^2 .

It is a cyclic number.

It is not a de Polignac number, because 666791817733 - 2⁵ = 666791817701 is a prime.

It is a super-2 number, since 2×666791817733² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666791817793) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333395908866 + 333395908867.

It is an arithmetic number, because the mean of its divisors is an integer number (333395908867).

Almost surely, 2^666791817733 is an apocalyptic number.

It is an amenable number.

666791817733 is a deficient number, since it is larger than the sum of its proper divisors (1).

666791817733 is an equidigital number, since it uses as much as digits as its factorization.

666791817733 is an evil number, because the sum of its binary digits is even.

The product of its digits is 48009024, while the sum is 64.

The spelling of 666791817733 in words is "six hundred sixty-six billion, seven hundred ninety-one million, eight hundred seventeen thousand, seven hundred thirty-three".