643932 has 36 divisors (see below), whose sum is σ = 1683136. Its totient is φ = 207360.

The previous prime is 643927. The next prime is 643949. The reversal of 643932 is 239346.

It is a tau number, because it is divible by the number of its divisors (36).

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 = 643896 and 643905.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 828 + ... + 1404.

2⁶⁴³⁹³² is an apocalyptic number.

643932 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 643932, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (841568).

643932 is an abundant number, since it is smaller than the sum of its proper divisors (1039204).

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

643932 is a wasteful number, since it uses less digits than its factorization.

643932 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 618 (or 613 counting only the distinct ones).

The product of its digits is 3888, while the sum is 27.

The square root of 643932 is about 802.4537369843. The cubic root of 643932 is about 86.3535115135.

The spelling of 643932 in words is "six hundred forty-three thousand, nine hundred thirty-two".