6663871 has 4 divisors (see below), whose sum is σ = 6673432. Its totient is φ = 6654312.

The previous prime is 6663869. The next prime is 6663893. The reversal of 6663871 is 1783666.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 6663871 - 2¹ = 6663869 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6663871.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6663841) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3645 + ... + 5158.

It is an arithmetic number, because the mean of its divisors is an integer number (1668358).

Almost surely, 2^6663871 is an apocalyptic number.

6663871 is a deficient number, since it is larger than the sum of its proper divisors (9561).

6663871 is an equidigital number, since it uses as much as digits as its factorization.

6663871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9560.

The product of its digits is 36288, while the sum is 37.

The square root of 6663871 is about 2581.4474621809. The cubic root of 6663871 is about 188.1808938673.

The spelling of 6663871 in words is "six million, six hundred sixty-three thousand, eight hundred seventy-one".