643161828 has 24 divisors (see below), whose sum is σ = 1521270688. Its totient is φ = 211450176.

The previous prime is 643161821. The next prime is 643161829. The reversal of 643161828 is 828161346.

It is not an unprimeable number, because it can be changed into a prime (643161821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 366226 + ... + 367977.

Almost surely, 2^643161828 is an apocalyptic number.

It is an amenable number.

643161828 is an abundant number, since it is smaller than the sum of its proper divisors (878108860).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

643161828 is a wasteful number, since it uses less digits than its factorization.

643161828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 734283 (or 734281 counting only the distinct ones).

The product of its digits is 55296, while the sum is 39.

The square root of 643161828 is about 25360.6354021345. The cubic root of 643161828 is about 863.1907020111.

The spelling of 643161828 in words is "six hundred forty-three million, one hundred sixty-one thousand, eight hundred twenty-eight".