643354561828 has 48 divisors (see below), whose sum is σ = 1322932343040. Its totient is φ = 270599767200.

The previous prime is 643354561807. The next prime is 643354561867. The reversal of 643354561828 is 828165453346.

643354561828 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8912458 + ... + 8984353.

It is an arithmetic number, because the mean of its divisors is an integer number (27561090480).

Almost surely, 2^643354561828 is an apocalyptic number.

It is an amenable number.

643354561828 is an abundant number, since it is smaller than the sum of its proper divisors (679577781212).

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

643354561828 is a wasteful number, since it uses less digits than its factorization.

643354561828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17896888 (or 17896886 counting only the distinct ones).

The product of its digits is 16588800, while the sum is 55.

The spelling of 643354561828 in words is "six hundred forty-three billion, three hundred fifty-four million, five hundred sixty-one thousand, eight hundred twenty-eight".