643917446 has 8 divisors (see below), whose sum is σ = 967731624. Its totient is φ = 321340240.

The previous prime is 643917433. The next prime is 643917473. The reversal of 643917446 is 644719346.

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

It is a junction number, because it is equal to n+sod(n) for n = 643917397 and 643917406.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 307940 + ... + 310023.

It is an arithmetic number, because the mean of its divisors is an integer number (120966453).

Almost surely, 2^643917446 is an apocalyptic number.

643917446 is a deficient number, since it is larger than the sum of its proper divisors (323814178).

643917446 is a wasteful number, since it uses less digits than its factorization.

643917446 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 618486.

The product of its digits is 435456, while the sum is 44.

The square root of 643917446 is about 25375.5284871074. The cubic root of 643917446 is about 863.5286092797.

The spelling of 643917446 in words is "six hundred forty-three million, nine hundred seventeen thousand, four hundred forty-six".