6643543471 has 2 divisors, whose sum is σ = 6643543472. Its totient is φ = 6643543470.

The previous prime is 6643543469. The next prime is 6643543507. The reversal of 6643543471 is 1743453466.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6643543471 - 2¹ = 6643543469 is a prime.

It is a super-3 number, since 3×6643543471³ (a number of 30 digits) contains 333 as substring.

Together with 6643543469, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6643543411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3321771735 + 3321771736.

It is an arithmetic number, because the mean of its divisors is an integer number (3321771736).

Almost surely, 2^6643543471 is an apocalyptic number.

6643543471 is a deficient number, since it is larger than the sum of its proper divisors (1).

6643543471 is an equidigital number, since it uses as much as digits as its factorization.

6643543471 is an evil number, because the sum of its binary digits is even.

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

The square root of 6643543471 is about 81507.9350186226. The cubic root of 6643543471 is about 1879.8935611046.

The spelling of 6643543471 in words is "six billion, six hundred forty-three million, five hundred forty-three thousand, four hundred seventy-one".