643373 has 2 divisors, whose sum is σ = 643374. Its totient is φ = 643372.

The previous prime is 643369. The next prime is 643403. The reversal of 643373 is 373346.

643373 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 643204 + 169 = 802^2 + 13^2 .

It is a cyclic number.

It is not a de Polignac number, because 643373 - 2² = 643369 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (643303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321686 + 321687.

It is an arithmetic number, because the mean of its divisors is an integer number (321687).

2⁶⁴³³⁷³ is an apocalyptic number.

It is an amenable number.

643373 is a deficient number, since it is larger than the sum of its proper divisors (1).

643373 is an equidigital number, since it uses as much as digits as its factorization.

643373 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4536, while the sum is 26.

The square root of 643373 is about 802.1053546761. The cubic root of 643373 is about 86.3285163339.

The spelling of 643373 in words is "six hundred forty-three thousand, three hundred seventy-three".