643613203 has 4 divisors (see below), whose sum is σ = 659311128. Its totient is φ = 627915280.

The previous prime is 643613177. The next prime is 643613221. The reversal of 643613203 is 302316346.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-643613203 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (643613233) 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 3 ways as a sum of consecutive naturals, for example, 7848901 + ... + 7848982.

It is an arithmetic number, because the mean of its divisors is an integer number (164827782).

Almost surely, 2^643613203 is an apocalyptic number.

643613203 is a deficient number, since it is larger than the sum of its proper divisors (15697925).

643613203 is a wasteful number, since it uses less digits than its factorization.

643613203 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15697924.

The product of its (nonzero) digits is 7776, while the sum is 28.

The square root of 643613203 is about 25369.5329677154. The cubic root of 643613203 is about 863.3925856714.

Adding to 643613203 its reverse (302316346), we get a palindrome (945929549).

The spelling of 643613203 in words is "six hundred forty-three million, six hundred thirteen thousand, two hundred three".