643303249 has 2 divisors, whose sum is σ = 643303250. Its totient is φ = 643303248.

The previous prime is 643303223. The next prime is 643303277. The reversal of 643303249 is 942303346.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 598144849 + 45158400 = 24457^2 + 6720^2 .

It is a cyclic number.

It is not a de Polignac number, because 643303249 - 2⁵ = 643303217 is a prime.

It is not a weakly prime, because it can be changed into another prime (643303049) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321651624 + 321651625.

It is an arithmetic number, because the mean of its divisors is an integer number (321651625).

Almost surely, 2^643303249 is an apocalyptic number.

It is an amenable number.

643303249 is a deficient number, since it is larger than the sum of its proper divisors (1).

643303249 is an equidigital number, since it uses as much as digits as its factorization.

643303249 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 46656, while the sum is 34.

The square root of 643303249 is about 25363.4234479496. The cubic root of 643303249 is about 863.2539646513.

The spelling of 643303249 in words is "six hundred forty-three million, three hundred three thousand, two hundred forty-nine".