643600 has 30 divisors (see below), whose sum is σ = 1547210. Its totient is φ = 257280.

The previous prime is 643589. The next prime is 643619. The reversal of 643600 is 6346.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 186624 + 456976 = 432^2 + 676^2 .

It is an unprimeable 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 5 ways as a sum of consecutive naturals, for example, 405 + ... + 1204.

2⁶⁴³⁶⁰⁰ is an apocalyptic number.

It is an amenable number.

643600 is an abundant number, since it is smaller than the sum of its proper divisors (903610).

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

643600 is a wasteful number, since it uses less digits than its factorization.

643600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1627 (or 1616 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 19.

The square root of 643600 is about 802.2468448053. The cubic root of 643600 is about 86.3386681789.

Adding to 643600 its reverse (6346), we get a palindrome (649946).

It can be divided in two parts, 64 and 3600, that multiplied together give a square (230400 = 480²).

The spelling of 643600 in words is "six hundred forty-three thousand, six hundred".