1664404019 has 2 divisors, whose sum is σ = 1664404020. Its totient is φ = 1664404018.

The previous prime is 1664404013. The next prime is 1664404031. The reversal of 1664404019 is 9104044661.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1664404019 - 2⁴ = 1664404003 is a prime.

It is a super-2 number, since 2×1664404019² = 5540481476926704722, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1664404019.

It is not a weakly prime, because it can be changed into another prime (1664404013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 832202009 + 832202010.

It is an arithmetic number, because the mean of its divisors is an integer number (832202010).

Almost surely, 2^1664404019 is an apocalyptic number.

1664404019 is a deficient number, since it is larger than the sum of its proper divisors (1).

1664404019 is an equidigital number, since it uses as much as digits as its factorization.

1664404019 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20736, while the sum is 35.

The square root of 1664404019 is about 40797.1079734826. The cubic root of 1664404019 is about 1185.0943254273.

The spelling of 1664404019 in words is "one billion, six hundred sixty-four million, four hundred four thousand, nineteen".