1664404013 has 2 divisors, whose sum is σ = 1664404014. Its totient is φ = 1664404012.

The previous prime is 1664404003. The next prime is 1664404019. The reversal of 1664404013 is 3104044661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1248774244 + 415629769 = 35338^2 + 20387^2 .

It is a cyclic number.

It is not a de Polignac number, because 1664404013 - 2¹² = 1664399917 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1664404019) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 832202006 + 832202007.

It is an arithmetic number, because the mean of its divisors is an integer number (832202007).

Almost surely, 2^1664404013 is an apocalyptic number.

It is an amenable number.

1664404013 is a deficient number, since it is larger than the sum of its proper divisors (1).

1664404013 is an equidigital number, since it uses as much as digits as its factorization.

1664404013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6912, while the sum is 29.

The square root of 1664404013 is about 40797.1078999480. The cubic root of 1664404013 is about 1185.0943240032.

Adding to 1664404013 its reverse (3104044661), we get a palindrome (4768448674).

The spelling of 1664404013 in words is "one billion, six hundred sixty-four million, four hundred four thousand, thirteen".