643718782962432 has 540 divisors, whose sum is σ = 2046532799102176. Its totient is φ = 201205276508160.

The previous prime is 643718782962427. The next prime is 643718782962433. The reversal of 643718782962432 is 234269287817346.

643718782962432 is a `hidden beast` number, since 6 + 4 + 3 + 7 + 187 + 8 + 2 + 9 + 6 + 2 + 432 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is not an unprimeable number, because it can be changed into a prime (643718782962433) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 1623824598 + ... + 1624220970.

Almost surely, 2^{643718782962432} 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 643718782962432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1023266399551088).

643718782962432 is an abundant number, since it is smaller than the sum of its proper divisors (1402814016139744).

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

643718782962432 is a wasteful number, since it uses less digits than its factorization.

643718782962432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 396706 (or 396666 counting only the distinct ones).

The product of its digits is 1170505728, while the sum is 72.

The spelling of 643718782962432 in words is "six hundred forty-three trillion, seven hundred eighteen billion, seven hundred eighty-two million, nine hundred sixty-two thousand, four hundred thirty-two".