643354793 has 2 divisors, whose sum is σ = 643354794. Its totient is φ = 643354792.

The previous prime is 643354771. The next prime is 643354843. The reversal of 643354793 is 397453346.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 592046224 + 51308569 = 24332^2 + 7163^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-643354793 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (643350793) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321677396 + 321677397.

It is an arithmetic number, because the mean of its divisors is an integer number (321677397).

Almost surely, 2^643354793 is an apocalyptic number.

It is an amenable number.

643354793 is a deficient number, since it is larger than the sum of its proper divisors (1).

643354793 is an equidigital number, since it uses as much as digits as its factorization.

643354793 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 816480, while the sum is 44.

The square root of 643354793 is about 25364.4395364849. The cubic root of 643354793 is about 863.2770198093.

The spelling of 643354793 in words is "six hundred forty-three million, three hundred fifty-four thousand, seven hundred ninety-three".