643004393 has 2 divisors, whose sum is σ = 643004394. Its totient is φ = 643004392.

The previous prime is 643004381. The next prime is 643004473. The reversal of 643004393 is 393400346.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 572309929 + 70694464 = 23923^2 + 8408^2 .

It is a cyclic number.

It is not a de Polignac number, because 643004393 - 2⁴ = 643004377 is a prime.

It is not a weakly prime, because it can be changed into another prime (643004363) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321502196 + 321502197.

It is an arithmetic number, because the mean of its divisors is an integer number (321502197).

Almost surely, 2^643004393 is an apocalyptic number.

It is an amenable number.

643004393 is a deficient number, since it is larger than the sum of its proper divisors (1).

643004393 is an equidigital number, since it uses as much as digits as its factorization.

643004393 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23328, while the sum is 32.

The square root of 643004393 is about 25357.5312875682. The cubic root of 643004393 is about 863.1202648302.

The spelling of 643004393 in words is "six hundred forty-three million, four thousand, three hundred ninety-three".