643396 has 12 divisors (see below), whose sum is σ = 1212652. Its totient is φ = 296928.

The previous prime is 643373. The next prime is 643403. The reversal of 643396 is 693346.

It can be written as a sum of positive squares in 2 ways, for example, as 202500 + 440896 = 450^2 + 664^2 .

It is a nialpdrome in base 15.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6135 + ... + 6238.

2⁶⁴³³⁹⁶ is an apocalyptic number.

It is an amenable number.

643396 is a deficient number, since it is larger than the sum of its proper divisors (569256).

643396 is a wasteful number, since it uses less digits than its factorization.

643396 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12390 (or 12388 counting only the distinct ones).

The product of its digits is 11664, while the sum is 31.

The square root of 643396 is about 802.1196918166. The cubic root of 643396 is about 86.3295450436.

The spelling of 643396 in words is "six hundred forty-three thousand, three hundred ninety-six".