643473385 has 8 divisors (see below), whose sum is σ = 772862400. Its totient is φ = 514315824.

The previous prime is 643473379. The next prime is 643473419. The reversal of 643473385 is 583374346.

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

It is a cyclic number.

It is not a de Polignac number, because 643473385 - 2³ = 643473377 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 51685 + ... + 62914.

It is an arithmetic number, because the mean of its divisors is an integer number (96607800).

Almost surely, 2^643473385 is an apocalyptic number.

It is an amenable number.

643473385 is a deficient number, since it is larger than the sum of its proper divisors (129389015).

643473385 is a wasteful number, since it uses less digits than its factorization.

643473385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115727.

The product of its digits is 725760, while the sum is 43.

The square root of 643473385 is about 25366.7771898600. Note that the first 3 decimals coincide. The cubic root of 643473385 is about 863.3300602464.

The spelling of 643473385 in words is "six hundred forty-three million, four hundred seventy-three thousand, three hundred eighty-five".