643674471 has 8 divisors (see below), whose sum is σ = 936253824. Its totient is φ = 390105720.

The previous prime is 643674469. The next prime is 643674491. The reversal of 643674471 is 174476346.

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

It is not a de Polignac number, because 643674471 - 2¹ = 643674469 is a prime.

It is a super-3 number, since 3×643674471³ (a number of 27 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643674431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9752611 + ... + 9752676.

It is an arithmetic number, because the mean of its divisors is an integer number (117031728).

Almost surely, 2^643674471 is an apocalyptic number.

643674471 is a deficient number, since it is larger than the sum of its proper divisors (292579353).

643674471 is a wasteful number, since it uses less digits than its factorization.

643674471 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19505301.

The product of its digits is 338688, while the sum is 42.

The square root of 643674471 is about 25370.7404503692. The cubic root of 643674471 is about 863.4199813485.

The spelling of 643674471 in words is "six hundred forty-three million, six hundred seventy-four thousand, four hundred seventy-one".