643471 has 8 divisors (see below), whose sum is σ = 680544. Its totient is φ = 607200.

The previous prime is 643469. The next prime is 643493. The reversal of 643471 is 174346.

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

It is not a de Polignac number, because 643471 - 2¹ = 643469 is a prime.

It is a super-3 number, since 3×643471³ = 799297015418328333, which contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2185 + ... + 2461.

It is an arithmetic number, because the mean of its divisors is an integer number (85068).

2⁶⁴³⁴⁷¹ is an apocalyptic number.

643471 is a deficient number, since it is larger than the sum of its proper divisors (37073).

643471 is a wasteful number, since it uses less digits than its factorization.

643471 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 401.

The product of its digits is 2016, while the sum is 25.

The square root of 643471 is about 802.1664415818. The cubic root of 643471 is about 86.3328993616.

The spelling of 643471 in words is "six hundred forty-three thousand, four hundred seventy-one".