643436345545 has 16 divisors (see below), whose sum is σ = 882524746368. Its totient is φ = 441164615040.

The previous prime is 643436345521. The next prime is 643436345581. The reversal of 643436345545 is 545543634346.

It is not a de Polignac number, because 643436345545 - 2²⁵ = 643402791113 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 643436345492 and 643436345501.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 696436 + ... + 1331125.

It is an arithmetic number, because the mean of its divisors is an integer number (55157796648).

Almost surely, 2^643436345545 is an apocalyptic number.

It is an amenable number.

643436345545 is a deficient number, since it is larger than the sum of its proper divisors (239088400823).

643436345545 is a wasteful number, since it uses less digits than its factorization.

643436345545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2036640.

The product of its digits is 31104000, while the sum is 52.

The spelling of 643436345545 in words is "six hundred forty-three billion, four hundred thirty-six million, three hundred forty-five thousand, five hundred forty-five".