643306463544 has 16 divisors (see below), whose sum is σ = 1608266158920. Its totient is φ = 214435487840.

The previous prime is 643306463467. The next prime is 643306463561. The reversal of 643306463544 is 445364603346.

643306463544 is digitally balanced in base 7, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 643306463493 and 643306463502.

It is a congruent 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, 13402217967 + ... + 13402218014.

Almost surely, 2^643306463544 is an apocalyptic number.

It is an amenable number.

643306463544 is an abundant number, since it is smaller than the sum of its proper divisors (964959695376).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

643306463544 is a wasteful number, since it uses less digits than its factorization.

643306463544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26804435990 (or 26804435986 counting only the distinct ones).

The product of its (nonzero) digits is 7464960, while the sum is 48.

The spelling of 643306463544 in words is "six hundred forty-three billion, three hundred six million, four hundred sixty-three thousand, five hundred forty-four".