666019 has 2 divisors, whose sum is σ = 666020. Its totient is φ = 666018.

The previous prime is 666013. The next prime is 666023. The reversal of 666019 is 910666.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 666019 - 2⁹ = 665507 is a prime.

It is a super-2 number, since 2×666019² = 887162616722, which contains 22 as substring.

It is a Chen prime.

666019 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (666013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333009 + 333010.

It is an arithmetic number, because the mean of its divisors is an integer number (333010).

2⁶⁶⁶⁰¹⁹ is an apocalyptic number.

666019 is a deficient number, since it is larger than the sum of its proper divisors (1).

666019 is an equidigital number, since it uses as much as digits as its factorization.

666019 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1944, while the sum is 28.

The square root of 666019 is about 816.0998713393. The cubic root of 666019 is about 87.3297478602.

The spelling of 666019 in words is "six hundred sixty-six thousand, nineteen".