643360 has 24 divisors (see below), whose sum is σ = 1520316. Its totient is φ = 257280.

The previous prime is 643303. The next prime is 643369. The reversal of 643360 is 63346.

It can be written as a sum of positive squares in 2 ways, for example, as 571536 + 71824 = 756^2 + 268^2 .

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (643369) by changing a digit.

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, 1851 + ... + 2170.

2⁶⁴³³⁶⁰ is an apocalyptic number.

It is an amenable number.

643360 is an abundant number, since it is smaller than the sum of its proper divisors (876956).

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

643360 is a wasteful number, since it uses less digits than its factorization.

643360 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4036 (or 4028 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 22.

The square root of 643360 is about 802.0972509615. The cubic root of 643360 is about 86.3279348784.

The spelling of 643360 in words is "six hundred forty-three thousand, three hundred sixty".