1664435449 has 2 divisors, whose sum is σ = 1664435450. Its totient is φ = 1664435448.

The previous prime is 1664435441. The next prime is 1664435453. The reversal of 1664435449 is 9445344661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1560803049 + 103632400 = 39507^2 + 10180^2 .

It is an emirp because it is prime and its reverse (9445344661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1664435449 - 2³ = 1664435441 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1664435399 and 1664435408.

It is not a weakly prime, because it can be changed into another prime (1664435441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 832217724 + 832217725.

It is an arithmetic number, because the mean of its divisors is an integer number (832217725).

Almost surely, 2^1664435449 is an apocalyptic number.

It is an amenable number.

1664435449 is a deficient number, since it is larger than the sum of its proper divisors (1).

1664435449 is an equidigital number, since it uses as much as digits as its factorization.

1664435449 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1244160, while the sum is 46.

The square root of 1664435449 is about 40797.4931705368. The cubic root of 1664435449 is about 1185.1017850103.

The spelling of 1664435449 in words is "one billion, six hundred sixty-four million, four hundred thirty-five thousand, four hundred forty-nine".