643442352242 has 8 divisors (see below), whose sum is σ = 965215194732. Its totient is φ = 321703954000.

The previous prime is 643442352229. The next prime is 643442352253. The reversal of 643442352242 is 242253244346.

It can be written as a sum of positive squares in 2 ways, for example, as 482439987241 + 161002365001 = 694579^2 + 401251^2 .

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

It is a self number, because there is not a number n which added to its sum of digits gives 643442352242.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8564309 + ... + 8639112.

Almost surely, 2^643442352242 is an apocalyptic number.

643442352242 is a deficient number, since it is larger than the sum of its proper divisors (321772842490).

643442352242 is a wasteful number, since it uses less digits than its factorization.

643442352242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17222124.

The product of its digits is 1105920, while the sum is 41.

Adding to 643442352242 its reverse (242253244346), we get a palindrome (885695596588).

The spelling of 643442352242 in words is "six hundred forty-three billion, four hundred forty-two million, three hundred fifty-two thousand, two hundred forty-two".