643613443 has 16 divisors (see below), whose sum is σ = 728258400. Its totient is φ = 563431680.

The previous prime is 643613437. The next prime is 643613459. The reversal of 643613443 is 344316346.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-643613443 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 643613399 and 643613408.

It is not an unprimeable number, because it can be changed into a prime (643613473) 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 15 ways as a sum of consecutive naturals, for example, 128005 + ... + 132937.

It is an arithmetic number, because the mean of its divisors is an integer number (45516150).

Almost surely, 2^643613443 is an apocalyptic number.

643613443 is a deficient number, since it is larger than the sum of its proper divisors (84644957).

643613443 is a wasteful number, since it uses less digits than its factorization.

643613443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5382.

The product of its digits is 62208, while the sum is 34.

The square root of 643613443 is about 25369.5376977981. The cubic root of 643613443 is about 863.3926929896.

Adding to 643613443 its reverse (344316346), we get a palindrome (987929789).

The spelling of 643613443 in words is "six hundred forty-three million, six hundred thirteen thousand, four hundred forty-three".