643356336 has 40 divisors (see below), whose sum is σ = 1899433984. Its totient is φ = 183816000.

The previous prime is 643356331. The next prime is 643356349. The reversal of 643356336 is 633653346.

It is a junction number, because it is equal to n+sod(n) for n = 643356294 and 643356303.

It is not an unprimeable number, because it can be changed into a prime (643356331) 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, 957040 + ... + 957711.

Almost surely, 2^643356336 is an apocalyptic number.

It is an amenable number.

643356336 is an abundant number, since it is smaller than the sum of its proper divisors (1256077648).

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

643356336 is a wasteful number, since it uses less digits than its factorization.

643356336 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1914769 (or 1914763 counting only the distinct ones).

The product of its digits is 349920, while the sum is 39.

The square root of 643356336 is about 25364.4699530662. The cubic root of 643356336 is about 863.2777099600.

The spelling of 643356336 in words is "six hundred forty-three million, three hundred fifty-six thousand, three hundred thirty-six".