643120 has 20 divisors (see below), whose sum is σ = 1495440. Its totient is φ = 257216.

The previous prime is 643099. The next prime is 643121. The reversal of 643120 is 21346.

It is a tau number, because it is divible by the number of its divisors (20).

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a junction number, because it is equal to n+sod(n) for n = 643094 and 643103.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643121) by changing a digit.

643120 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3940 + ... + 4099.

It is an arithmetic number, because the mean of its divisors is an integer number (74772).

2⁶⁴³¹²⁰ is an apocalyptic number.

It is an amenable number.

643120 is an abundant number, since it is smaller than the sum of its proper divisors (852320).

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

643120 is a wasteful number, since it uses less digits than its factorization.

643120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8052 (or 8046 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 643120 is about 801.9476292128. The cubic root of 643120 is about 86.3171989083.

Adding to 643120 its reverse (21346), we get a palindrome (664466).

The spelling of 643120 in words is "six hundred forty-three thousand, one hundred twenty".