643679232 has 176 divisors, whose sum is σ = 2016213120. Its totient is φ = 178716672.

The previous prime is 643679227. The next prime is 643679233. The reversal of 643679232 is 232976346.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is not an unprimeable number, because it can be changed into a prime (643679233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 795244 + ... + 796052.

Almost surely, 2^643679232 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 643679232, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1008106560).

643679232 is an abundant number, since it is smaller than the sum of its proper divisors (1372533888).

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

643679232 is a wasteful number, since it uses less digits than its factorization.

643679232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 876 (or 858 counting only the distinct ones).

The product of its digits is 326592, while the sum is 42.

The square root of 643679232 is about 25370.8342787540. The cubic root of 643679232 is about 863.4221101329.

The spelling of 643679232 in words is "six hundred forty-three million, six hundred seventy-nine thousand, two hundred thirty-two".