643147344 has 240 divisors, whose sum is σ = 2242535040. Its totient is φ = 175633920.

The previous prime is 643147343. The next prime is 643147363. The reversal of 643147344 is 443741346.

643147344 is a `hidden beast` number, since 643 + 1 + 4 + 7 + 3 + 4 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 643147299 and 643147308.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643147343) 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 47 ways as a sum of consecutive naturals, for example, 486204 + ... + 487524.

It is an arithmetic number, because the mean of its divisors is an integer number (9343896).

Almost surely, 2^643147344 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 643147344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1121267520).

643147344 is an abundant number, since it is smaller than the sum of its proper divisors (1599387696).

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

643147344 is a wasteful number, since it uses less digits than its factorization.

643147344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1375 (or 1356 counting only the distinct ones).

The product of its digits is 96768, while the sum is 36.

The square root of 643147344 is about 25360.3498398583. The cubic root of 643147344 is about 863.1842222795.

The spelling of 643147344 in words is "six hundred forty-three million, one hundred forty-seven thousand, three hundred forty-four".