643321067 has 4 divisors (see below), whose sum is σ = 653867376. Its totient is φ = 632774760.

The previous prime is 643321027. The next prime is 643321093. The reversal of 643321067 is 760123346.

643321067 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 643321067 - 2¹⁶ = 643255531 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (643321027) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5273063 + ... + 5273184.

It is an arithmetic number, because the mean of its divisors is an integer number (163466844).

Almost surely, 2^643321067 is an apocalyptic number.

643321067 is a deficient number, since it is larger than the sum of its proper divisors (10546309).

643321067 is a wasteful number, since it uses less digits than its factorization.

643321067 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10546308.

The product of its (nonzero) digits is 18144, while the sum is 32.

The square root of 643321067 is about 25363.7746993621. The cubic root of 643321067 is about 863.2619346184.

The spelling of 643321067 in words is "six hundred forty-three million, three hundred twenty-one thousand, sixty-seven".