643243 has 2 divisors, whose sum is σ = 643244. Its totient is φ = 643242.

The previous prime is 643231. The next prime is 643273. The reversal of 643243 is 342346.

643243 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 is a cyclic number.

It is not a de Polignac number, because 643243 - 2¹³ = 635051 is a prime.

It is not a weakly prime, because it can be changed into another prime (643213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321621 + 321622.

It is an arithmetic number, because the mean of its divisors is an integer number (321622).

2⁶⁴³²⁴³ is an apocalyptic number.

643243 is a deficient number, since it is larger than the sum of its proper divisors (1).

643243 is an equidigital number, since it uses as much as digits as its factorization.

643243 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1728, while the sum is 22.

The square root of 643243 is about 802.0243138459. The cubic root of 643243 is about 86.3227014266.

Adding to 643243 its reverse (342346), we get a palindrome (985589).

The spelling of 643243 in words is "six hundred forty-three thousand, two hundred forty-three".