643161792 has 224 divisors, whose sum is σ = 2117896704. Its totient is φ = 167731200.

The previous prime is 643161791. The next prime is 643161821. The reversal of 643161792 is 297161346.

643161792 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (224).

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a self number, because there is not a number n which added to its sum of digits gives 643161792.

It is not an unprimeable number, because it can be changed into a prime (643161791) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2288692 + ... + 2288972.

It is an arithmetic number, because the mean of its divisors is an integer number (9454896).

Almost surely, 2^643161792 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 643161792, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1058948352).

643161792 is an abundant number, since it is smaller than the sum of its proper divisors (1474734912).

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

643161792 is a wasteful number, since it uses less digits than its factorization.

643161792 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 447 (or 437 counting only the distinct ones).

The product of its digits is 54432, while the sum is 39.

The square root of 643161792 is about 25360.6346923731. The cubic root of 643161792 is about 863.1906859058.

The spelling of 643161792 in words is "six hundred forty-three million, one hundred sixty-one thousand, seven hundred ninety-two".