643473384 has 64 divisors (see below), whose sum is σ = 1640520000. Its totient is φ = 210270720.

The previous prime is 643473379. The next prime is 643473419. The reversal of 643473384 is 483374346.

It is a super-2 number, since 2×643473384² = 828115991832822912, which contains 22 as substring.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 612892 + ... + 613940.

It is an arithmetic number, because the mean of its divisors is an integer number (25633125).

Almost surely, 2^643473384 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 643473384, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (820260000).

643473384 is an abundant number, since it is smaller than the sum of its proper divisors (997046616).

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

643473384 is a wasteful number, since it uses less digits than its factorization.

643473384 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1538 (or 1534 counting only the distinct ones).

The product of its digits is 580608, while the sum is 42.

The square root of 643473384 is about 25366.7771701491. Note that the first 3 decimals coincide. The cubic root of 643473384 is about 863.3300597992.

The spelling of 643473384 in words is "six hundred forty-three million, four hundred seventy-three thousand, three hundred eighty-four".