643122432 has 108 divisors (see below), whose sum is σ = 1894052160. Its totient is φ = 209777664.

The previous prime is 643122391. The next prime is 643122443. The reversal of 643122432 is 234221346.

643122432 is a `hidden beast` number, since 6 + 431 + 224 + 3 + 2 = 666.

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 643122396 and 643122405.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 105319 + ... + 111257.

It is an arithmetic number, because the mean of its divisors is an integer number (17537520).

Almost surely, 2^643122432 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 643122432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (947026080).

643122432 is an abundant number, since it is smaller than the sum of its proper divisors (1250929728).

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

643122432 is a wasteful number, since it uses less digits than its factorization.

643122432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6008 (or 5991 counting only the distinct ones).

The product of its digits is 6912, while the sum is 27.

The square root of 643122432 is about 25359.8586746851. The cubic root of 643122432 is about 863.1730771284.

Adding to 643122432 its reverse (234221346), we get a palindrome (877343778).

The spelling of 643122432 in words is "six hundred forty-three million, one hundred twenty-two thousand, four hundred thirty-two".