1280644019 has 2 divisors, whose sum is σ = 1280644020. Its totient is φ = 1280644018.

The previous prime is 1280643941. The next prime is 1280644049. The reversal of 1280644019 is 9104460821.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1280644019 - 2²⁴ = 1263866803 is a prime.

It is a super-2 number, since 2×1280644019² = 3280098206800944722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1280644019.

It is not a weakly prime, because it can be changed into another prime (1280644049) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 640322009 + 640322010.

It is an arithmetic number, because the mean of its divisors is an integer number (640322010).

Almost surely, 2^1280644019 is an apocalyptic number.

1280644019 is a deficient number, since it is larger than the sum of its proper divisors (1).

1280644019 is an equidigital number, since it uses as much as digits as its factorization.

1280644019 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13824, while the sum is 35.

The square root of 1280644019 is about 35786.0869473040. The cubic root of 1280644019 is about 1085.9491136604.

The spelling of 1280644019 in words is "one billion, two hundred eighty million, six hundred forty-four thousand, nineteen".