643789104 has 80 divisors (see below), whose sum is σ = 1913448960. Its totient is φ = 182707200.

The previous prime is 643789087. The next prime is 643789109. The reversal of 643789104 is 401987346.

643789104 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is not an unprimeable number, because it can be changed into a prime (643789109) 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, 44392 + ... + 57080.

It is an arithmetic number, because the mean of its divisors is an integer number (23918112).

Almost surely, 2^643789104 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 643789104, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (956724480).

643789104 is an abundant number, since it is smaller than the sum of its proper divisors (1269659856).

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

643789104 is a wasteful number, since it uses less digits than its factorization.

643789104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12858 (or 12852 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 42.

The square root of 643789104 is about 25372.9995073503. Note that the first 3 decimals coincide. The cubic root of 643789104 is about 863.4712342474.

The spelling of 643789104 in words is "six hundred forty-three million, seven hundred eighty-nine thousand, one hundred four".