643505626336 has 48 divisors (see below), whose sum is σ = 1311496431840. Its totient is φ = 310442549760.

The previous prime is 643505626333. The next prime is 643505626349. The reversal of 643505626336 is 633626505346.

It is a super-2 number, since 2×643505626336² (a number of 24 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 643505626336.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643505626333) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1103206 + ... + 1582426.

It is an arithmetic number, because the mean of its divisors is an integer number (27322842330).

Almost surely, 2^643505626336 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 643505626336, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (655748215920).

643505626336 is an abundant number, since it is smaller than the sum of its proper divisors (667990805504).

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

643505626336 is a wasteful number, since it uses less digits than its factorization.

643505626336 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 480707 (or 480699 counting only the distinct ones).

The product of its (nonzero) digits is 6998400, while the sum is 49.

The spelling of 643505626336 in words is "six hundred forty-three billion, five hundred five million, six hundred twenty-six thousand, three hundred thirty-six".