643511445216 has 24 divisors (see below), whose sum is σ = 1689217543944. Its totient is φ = 214503815040.

The previous prime is 643511445197. The next prime is 643511445217. The reversal of 643511445216 is 612544115346.

It is a tau number, because it is divible by the number of its divisors (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643511445217) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3351622015 + ... + 3351622206.

It is an arithmetic number, because the mean of its divisors is an integer number (70384064331).

Almost surely, 2^643511445216 is an apocalyptic number.

It is an amenable number.

643511445216 is an abundant number, since it is smaller than the sum of its proper divisors (1045706098728).

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

643511445216 is a wasteful number, since it uses less digits than its factorization.

643511445216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6703244234 (or 6703244226 counting only the distinct ones).

The product of its digits is 345600, while the sum is 42.

The spelling of 643511445216 in words is "six hundred forty-three billion, five hundred eleven million, four hundred forty-five thousand, two hundred sixteen".