1643344463 has 2 divisors, whose sum is σ = 1643344464. Its totient is φ = 1643344462.

The previous prime is 1643344387. The next prime is 1643344471. The reversal of 1643344463 is 3644433461.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1643344463 - 2⁸ = 1643344207 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1643344063) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 821672231 + 821672232.

It is an arithmetic number, because the mean of its divisors is an integer number (821672232).

Almost surely, 2^1643344463 is an apocalyptic number.

1643344463 is a deficient number, since it is larger than the sum of its proper divisors (1).

1643344463 is an equidigital number, since it uses as much as digits as its factorization.

1643344463 is an evil number, because the sum of its binary digits is even.

The product of its digits is 248832, while the sum is 38.

The square root of 1643344463 is about 40538.1852455188. The cubic root of 1643344463 is about 1180.0747972792.

The spelling of 1643344463 in words is "one billion, six hundred forty-three million, three hundred forty-four thousand, four hundred sixty-three".