643968002 has 8 divisors (see below), whose sum is σ = 966265212. Its totient is φ = 321879600.

The previous prime is 643968001. The next prime is 643968019. The reversal of 643968002 is 200869346.

It can be written as a sum of positive squares in 2 ways, for example, as 449058481 + 194909521 = 21191^2 + 13961^2 .

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

It is not an unprimeable number, because it can be changed into a prime (643968001) 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, 44249 + ... + 56972.

Almost surely, 2^643968002 is an apocalyptic number.

643968002 is a deficient number, since it is larger than the sum of its proper divisors (322297210).

643968002 is a wasteful number, since it uses less digits than its factorization.

643968002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104404.

The product of its (nonzero) digits is 62208, while the sum is 38.

The square root of 643968002 is about 25376.5246241482. The cubic root of 643968002 is about 863.5512081444.

The spelling of 643968002 in words is "six hundred forty-three million, nine hundred sixty-eight thousand, two".