643513305439 has 2 divisors, whose sum is σ = 643513305440. Its totient is φ = 643513305438.

The previous prime is 643513305419. The next prime is 643513305499. The reversal of 643513305439 is 934503315346.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 643513305439 - 2²⁵ = 643479751007 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (643513305419) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321756652719 + 321756652720.

It is an arithmetic number, because the mean of its divisors is an integer number (321756652720).

Almost surely, 2^643513305439 is an apocalyptic number.

643513305439 is a deficient number, since it is larger than the sum of its proper divisors (1).

643513305439 is an equidigital number, since it uses as much as digits as its factorization.

643513305439 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1749600, while the sum is 46.

The spelling of 643513305439 in words is "six hundred forty-three billion, five hundred thirteen million, three hundred five thousand, four hundred thirty-nine".