643853948 has 6 divisors (see below), whose sum is σ = 1126744416. Its totient is φ = 321926972.

The previous prime is 643853939. The next prime is 643853981. The reversal of 643853948 is 849358346.

It is a happy number.

643853948 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 643853896 and 643853905.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80481740 + ... + 80481747.

It is an arithmetic number, because the mean of its divisors is an integer number (187790736).

Almost surely, 2^643853948 is an apocalyptic number.

It is an amenable number.

643853948 is a deficient number, since it is larger than the sum of its proper divisors (482890468).

643853948 is a wasteful number, since it uses less digits than its factorization.

643853948 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160963491 (or 160963489 counting only the distinct ones).

The product of its digits is 2488320, while the sum is 50.

The square root of 643853948 is about 25374.2772902008. The cubic root of 643853948 is about 863.5002235798.

The spelling of 643853948 in words is "six hundred forty-three million, eight hundred fifty-three thousand, nine hundred forty-eight".