643104 has 144 divisors (see below), whose sum is σ = 2358720. Its totient is φ = 161280.

The previous prime is 643099. The next prime is 643121. The reversal of 643104 is 401346.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

643104 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 22162 + ... + 22190.

It is an arithmetic number, because the mean of its divisors is an integer number (16380).

2⁶⁴³¹⁰⁴ 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 643104, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1179360).

643104 is an abundant number, since it is smaller than the sum of its proper divisors (1715616).

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

643104 is a wasteful number, since it uses less digits than its factorization.

643104 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63 (or 52 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 643104 is about 801.9376534370. The cubic root of 643104 is about 86.3164830820.

It can be divided in two parts, 643 and 104, that added together give a palindrome (747).

The spelling of 643104 in words is "six hundred forty-three thousand, one hundred four".