643772203 has 4 divisors (see below), whose sum is σ = 649678480. Its totient is φ = 637865928.

The previous prime is 643772191. The next prime is 643772273. The reversal of 643772203 is 302277346.

It is a happy number.

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-643772203 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (643772273) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2952975 + ... + 2953192.

It is an arithmetic number, because the mean of its divisors is an integer number (162419620).

Almost surely, 2^643772203 is an apocalyptic number.

643772203 is a deficient number, since it is larger than the sum of its proper divisors (5906277).

643772203 is a wasteful number, since it uses less digits than its factorization.

643772203 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5906276.

The product of its (nonzero) digits is 42336, while the sum is 34.

The square root of 643772203 is about 25372.6664542771. Note that the first 3 decimals coincide. The cubic root of 643772203 is about 863.4636781212.

The spelling of 643772203 in words is "six hundred forty-three million, seven hundred seventy-two thousand, two hundred three".