643068329 has 2 divisors, whose sum is σ = 643068330. Its totient is φ = 643068328.

The previous prime is 643068323. The next prime is 643068347. The reversal of 643068329 is 923860346.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 567725929 + 75342400 = 23827^2 + 8680^2 .

It is a cyclic number.

It is not a de Polignac number, because 643068329 - 2¹⁶ = 643002793 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (643068323) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321534164 + 321534165.

It is an arithmetic number, because the mean of its divisors is an integer number (321534165).

Almost surely, 2^643068329 is an apocalyptic number.

It is an amenable number.

643068329 is a deficient number, since it is larger than the sum of its proper divisors (1).

643068329 is an equidigital number, since it uses as much as digits as its factorization.

643068329 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 186624, while the sum is 41.

The square root of 643068329 is about 25358.7919467785. The cubic root of 643068329 is about 863.1488714923.

The spelling of 643068329 in words is "six hundred forty-three million, sixty-eight thousand, three hundred twenty-nine".