664251019 has 2 divisors, whose sum is σ = 664251020. Its totient is φ = 664251018.

The previous prime is 664250989. The next prime is 664251037. The reversal of 664251019 is 910152466.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 664251019 - 2⁷ = 664250891 is a prime.

It is a super-2 number, since 2×664251019² = 882458832485076722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (664251059) 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, 332125509 + 332125510.

It is an arithmetic number, because the mean of its divisors is an integer number (332125510).

Almost surely, 2^664251019 is an apocalyptic number.

664251019 is a deficient number, since it is larger than the sum of its proper divisors (1).

664251019 is an equidigital number, since it uses as much as digits as its factorization.

664251019 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12960, while the sum is 34.

The square root of 664251019 is about 25773.0677064256. The cubic root of 664251019 is about 872.5240564463.

The spelling of 664251019 in words is "six hundred sixty-four million, two hundred fifty-one thousand, nineteen".