6623 has 4 divisors (see below), whose sum is σ = 6840. Its totient is φ = 6408.

The previous prime is 6619. The next prime is 6637. The reversal of 6623 is 3266.

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 6623 - 2² = 6619 is a prime.

It is a Duffinian number.

Its product of digits (216) is a multiple of the sum of its prime divisors (216).

It is a plaindrome in base 12 and base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6653) 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, 53 + ... + 126.

It is an arithmetic number, because the mean of its divisors is an integer number (1710).

2⁶⁶²³ is an apocalyptic number.

6623 is the 44-th centered heptagonal number.

6623 is a deficient number, since it is larger than the sum of its proper divisors (217).

6623 is a wasteful number, since it uses less digits than its factorization.

6623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 216.

The product of its digits is 216, while the sum is 17.

The square root of 6623 is about 81.3818161508. The cubic root of 6623 is about 18.7795386258.

Adding to 6623 its reverse (3266), we get a palindrome (9889).

The spelling of 6623 in words is "six thousand, six hundred twenty-three".