643310534305 has 4 divisors (see below), whose sum is σ = 771972641172. Its totient is φ = 514648427440.

The previous prime is 643310534297. The next prime is 643310534323. The reversal of 643310534305 is 503435013346.

643310534305 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 500798244241 + 142512290064 = 707671^2 + 377508^2 .

It is not a de Polignac number, because 643310534305 - 2³ = 643310534297 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64331053426 + ... + 64331053435.

It is an arithmetic number, because the mean of its divisors is an integer number (192993160293).

Almost surely, 2^643310534305 is an apocalyptic number.

It is an amenable number.

643310534305 is a deficient number, since it is larger than the sum of its proper divisors (128662106867).

643310534305 is a wasteful number, since it uses less digits than its factorization.

643310534305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128662106866.

The product of its (nonzero) digits is 194400, while the sum is 37.

The spelling of 643310534305 in words is "six hundred forty-three billion, three hundred ten million, five hundred thirty-four thousand, three hundred five".