643661253325203 has 8 divisors (see below), whose sum is σ = 869971374357648. Its totient is φ = 423229317254784.

The previous prime is 643661253325147. The next prime is 643661253325229. The reversal of 643661253325203 is 302523352166346.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 643661253325203 - 2²² = 643661249130899 is a prime.

It is not an unprimeable number, because it can be changed into a prime (643661253323203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1469546240250 + ... + 1469546240687.

It is an arithmetic number, because the mean of its divisors is an integer number (108746421794706).

Almost surely, 2^{643661253325203} is an apocalyptic number.

643661253325203 is a deficient number, since it is larger than the sum of its proper divisors (226310121032445).

643661253325203 is a wasteful number, since it uses less digits than its factorization.

643661253325203 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2939092481013.

The product of its (nonzero) digits is 13996800, while the sum is 51.

The spelling of 643661253325203 in words is "six hundred forty-three trillion, six hundred sixty-one billion, two hundred fifty-three million, three hundred twenty-five thousand, two hundred three".