1643591743 has 2 divisors, whose sum is σ = 1643591744. Its totient is φ = 1643591742.

The previous prime is 1643591711. The next prime is 1643591749. The reversal of 1643591743 is 3471953461.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1643591743 - 2⁵ = 1643591711 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1643591743.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1643591749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 821795871 + 821795872.

It is an arithmetic number, because the mean of its divisors is an integer number (821795872).

Almost surely, 2^1643591743 is an apocalyptic number.

1643591743 is a deficient number, since it is larger than the sum of its proper divisors (1).

1643591743 is an equidigital number, since it uses as much as digits as its factorization.

1643591743 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 272160, while the sum is 43.

The square root of 1643591743 is about 40541.2350946539. The cubic root of 1643591743 is about 1180.1339843551.

The spelling of 1643591743 in words is "one billion, six hundred forty-three million, five hundred ninety-one thousand, seven hundred forty-three".