666034721621219 has 2 divisors, whose sum is σ = 666034721621220. Its totient is φ = 666034721621218.

The previous prime is 666034721621183. The next prime is 666034721621233. The reversal of 666034721621219 is 912126127430666.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 666034721621219 - 2⁸ = 666034721620963 is a prime.

It is a super-2 number, since 2×666034721621219² (a number of 30 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (666034721621239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333017360810609 + 333017360810610.

It is an arithmetic number, because the mean of its divisors is an integer number (333017360810610).

Almost surely, 2^{666034721621219} is an apocalyptic number.

666034721621219 is a deficient number, since it is larger than the sum of its proper divisors (1).

666034721621219 is an equidigital number, since it uses as much as digits as its factorization.

666034721621219 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7838208, while the sum is 56.

The spelling of 666034721621219 in words is "six hundred sixty-six trillion, thirty-four billion, seven hundred twenty-one million, six hundred twenty-one thousand, two hundred nineteen".