643080778512 has 80 divisors (see below), whose sum is σ = 1677726630528. Its totient is φ = 212240424960.

The previous prime is 643080778507. The next prime is 643080778531. The reversal of 643080778512 is 215877080346.

643080778512 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, 42713578 + ... + 42728630.

Almost surely, 2^643080778512 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 643080778512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (838863315264).

643080778512 is an abundant number, since it is smaller than the sum of its proper divisors (1034645852016).

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

643080778512 is a wasteful number, since it uses less digits than its factorization.

643080778512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23808 (or 23802 counting only the distinct ones).

The product of its (nonzero) digits is 2257920, while the sum is 51.

The spelling of 643080778512 in words is "six hundred forty-three billion, eighty million, seven hundred seventy-eight thousand, five hundred twelve".