643728622 has 8 divisors (see below), whose sum is σ = 968182776. Its totient is φ = 321001032.

The previous prime is 643728611. The next prime is 643728649. The reversal of 643728622 is 226827346.

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

It is a congruent number.

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, 430708 + ... + 432199.

It is an arithmetic number, because the mean of its divisors is an integer number (121022847).

Almost surely, 2^643728622 is an apocalyptic number.

643728622 is a deficient number, since it is larger than the sum of its proper divisors (324454154).

643728622 is a wasteful number, since it uses less digits than its factorization.

643728622 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 863282.

The product of its digits is 193536, while the sum is 40.

The square root of 643728622 is about 25371.8076218467. The cubic root of 643728622 is about 863.4441932478. Note that the first 3 decimals are identical.

The spelling of 643728622 in words is "six hundred forty-three million, seven hundred twenty-eight thousand, six hundred twenty-two".