664019 has 2 divisors, whose sum is σ = 664020. Its totient is φ = 664018.

The previous prime is 664009. The next prime is 664043. The reversal of 664019 is 910466.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 664019 - 2⁸ = 663763 is a prime.

It is a super-2 number, since 2×664019² = 881842464722, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (664009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332009 + 332010.

It is an arithmetic number, because the mean of its divisors is an integer number (332010).

2⁶⁶⁴⁰¹⁹ is an apocalyptic number.

664019 is a deficient number, since it is larger than the sum of its proper divisors (1).

664019 is an equidigital number, since it uses as much as digits as its factorization.

664019 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 26.

The square root of 664019 is about 814.8736098316. The cubic root of 664019 is about 87.2422455431.

The spelling of 664019 in words is "six hundred sixty-four thousand, nineteen".