643474368 has 280 divisors, whose sum is σ = 2065324800. Its totient is φ = 197448192.

The previous prime is 643474357. The next prime is 643474369. The reversal of 643474368 is 863474346.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643474369) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 4629243 + ... + 4629381.

It is an arithmetic number, because the mean of its divisors is an integer number (7376160).

Almost surely, 2^643474368 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 643474368, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1032662400).

643474368 is an abundant number, since it is smaller than the sum of its proper divisors (1421850432).

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

643474368 is a wasteful number, since it uses less digits than its factorization.

643474368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229 (or 210 counting only the distinct ones).

The product of its digits is 1161216, while the sum is 45.

The square root of 643474368 is about 25366.7965655894. The cubic root of 643474368 is about 863.3304998673.

The spelling of 643474368 in words is "six hundred forty-three million, four hundred seventy-four thousand, three hundred sixty-eight".