643599432 has 320 divisors, whose sum is σ = 2230272000. Its totient is φ = 169361280.

The previous prime is 643599431. The next prime is 643599479. The reversal of 643599432 is 234995346.

It is not an unprimeable number, because it can be changed into a prime (643599431) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 3234069 + ... + 3234267.

It is an arithmetic number, because the mean of its divisors is an integer number (6969600).

Almost surely, 2^643599432 is an apocalyptic number.

643599432 is a gapful number since it is divisible by the number (62) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 643599432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1115136000).

643599432 is an abundant number, since it is smaller than the sum of its proper divisors (1586672568).

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

643599432 is a wasteful number, since it uses less digits than its factorization.

643599432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 278 (or 265 counting only the distinct ones).

The product of its digits is 699840, while the sum is 45.

The square root of 643599432 is about 25369.2615580351. The cubic root of 643599432 is about 863.3864277989.

The spelling of 643599432 in words is "six hundred forty-three million, five hundred ninety-nine thousand, four hundred thirty-two".