641643518 has 12 divisors (see below), whose sum is σ = 993821472. Its totient is φ = 310376160.

The previous prime is 641643503. The next prime is 641643521. The reversal of 641643518 is 815346146.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 197846 + ... + 201062.

It is an arithmetic number, because the mean of its divisors is an integer number (82818456).

Almost surely, 2^641643518 is an apocalyptic number.

641643518 is a deficient number, since it is larger than the sum of its proper divisors (352177954).

641643518 is an frugal number, since it uses more digits than its factorization.

641643518 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6467 (or 3250 counting only the distinct ones).

The product of its digits is 69120, while the sum is 38.

The square root of 641643518 is about 25330.6833306960. The cubic root of 641643518 is about 862.5109230011.

The spelling of 641643518 in words is "six hundred forty-one million, six hundred forty-three thousand, five hundred eighteen".