1005643 has 2 divisors, whose sum is σ = 1005644. Its totient is φ = 1005642.

The previous prime is 1005637. The next prime is 1005647. The reversal of 1005643 is 3465001.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1005643 - 2⁹ = 1005131 is a prime.

It is a super-2 number, since 2×1005643² = 2022635686898, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1005643.

It is not a weakly prime, because it can be changed into another prime (1005647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 502821 + 502822.

It is an arithmetic number, because the mean of its divisors is an integer number (502822).

2^1005643 is an apocalyptic number.

1005643 is a deficient number, since it is larger than the sum of its proper divisors (1).

1005643 is an equidigital number, since it uses as much as digits as its factorization.

1005643 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 360, while the sum is 19.

The square root of 1005643 is about 1002.8175307602. The cubic root of 1005643 is about 100.1877472890.

The spelling of 1005643 in words is "one million, five thousand, six hundred forty-three".