643326873 has 16 divisors (see below), whose sum is σ = 990016896. Its totient is φ = 363974400.

The previous prime is 643326863. The next prime is 643326899. The reversal of 643326873 is 378623346.

It is not a de Polignac number, because 643326873 - 2⁸ = 643326617 is a prime.

It is not an unprimeable number, because it can be changed into a prime (643326823) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 149536 + ... + 153777.

It is an arithmetic number, because the mean of its divisors is an integer number (61876056).

Almost surely, 2^643326873 is an apocalyptic number.

It is an amenable number.

643326873 is a deficient number, since it is larger than the sum of its proper divisors (346690023).

643326873 is a wasteful number, since it uses less digits than its factorization.

643326873 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 303424.

The product of its digits is 435456, while the sum is 42.

The square root of 643326873 is about 25363.8891536767. The cubic root of 643326873 is about 863.2645316025.

The spelling of 643326873 in words is "six hundred forty-three million, three hundred twenty-six thousand, eight hundred seventy-three".