666215219 has 2 divisors, whose sum is σ = 666215220. Its totient is φ = 666215218.

The previous prime is 666215201. The next prime is 666215257. The reversal of 666215219 is 912512666.

It is an a-pointer prime, because the next prime (666215257) can be obtained adding 666215219 to its sum of digits (38).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 666215219 - 2¹⁶ = 666149683 is a prime.

It is a super-2 number, since 2×666215219² = 887685436054435922, which contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (666215279) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333107609 + 333107610.

It is an arithmetic number, because the mean of its divisors is an integer number (333107610).

Almost surely, 2^666215219 is an apocalyptic number.

666215219 is a deficient number, since it is larger than the sum of its proper divisors (1).

666215219 is an equidigital number, since it uses as much as digits as its factorization.

666215219 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 38880, while the sum is 38.

The square root of 666215219 is about 25811.1452477413. The cubic root of 666215219 is about 873.3832322783.

The spelling of 666215219 in words is "six hundred sixty-six million, two hundred fifteen thousand, two hundred nineteen".