643523347 has 2 divisors, whose sum is σ = 643523348. Its totient is φ = 643523346.

The previous prime is 643523341. The next prime is 643523381. The reversal of 643523347 is 743325346.

643523347 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-643523347 is a prime.

It is not a weakly prime, because it can be changed into another prime (643523341) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321761673 + 321761674.

It is an arithmetic number, because the mean of its divisors is an integer number (321761674).

Almost surely, 2^643523347 is an apocalyptic number.

643523347 is a deficient number, since it is larger than the sum of its proper divisors (1).

643523347 is an equidigital number, since it uses as much as digits as its factorization.

643523347 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 181440, while the sum is 37.

The square root of 643523347 is about 25367.7619627747. The cubic root of 643523347 is about 863.3524038694.

The spelling of 643523347 in words is "six hundred forty-three million, five hundred twenty-three thousand, three hundred forty-seven".