643140445612 has 48 divisors (see below), whose sum is σ = 1318726886400. Its totient is φ = 268689859200.

The previous prime is 643140445579. The next prime is 643140445669. The reversal of 643140445612 is 216544041346.

It is a happy number.

643140445612 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, 1185639 + ... + 1640737.

It is an arithmetic number, because the mean of its divisors is an integer number (27473476800).

Almost surely, 2^643140445612 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 643140445612, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (659363443200).

643140445612 is an abundant number, since it is smaller than the sum of its proper divisors (675586440788).

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

643140445612 is a wasteful number, since it uses less digits than its factorization.

643140445612 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 456382 (or 456380 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 40.

Adding to 643140445612 its reverse (216544041346), we get a palindrome (859684486958).

The spelling of 643140445612 in words is "six hundred forty-three billion, one hundred forty million, four hundred forty-five thousand, six hundred twelve".