6621023 has 4 divisors (see below), whose sum is σ = 6626568. Its totient is φ = 6615480.

The previous prime is 6620981. The next prime is 6621029. The reversal of 6621023 is 3201266.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 3201266 = 2 ⋅1600633.

It is a cyclic number.

It is not a de Polignac number, because 6621023 - 2¹⁴ = 6604639 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6620986 and 6621004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6621029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 161 + ... + 3642.

It is an arithmetic number, because the mean of its divisors is an integer number (1656642).

Almost surely, 2^6621023 is an apocalyptic number.

6621023 is a deficient number, since it is larger than the sum of its proper divisors (5545).

6621023 is a wasteful number, since it uses less digits than its factorization.

6621023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5544.

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 6621023 is about 2573.1348584946. The cubic root of 6621023 is about 187.7766984313.

Adding to 6621023 its reverse (3201266), we get a palindrome (9822289).

The spelling of 6621023 in words is "six million, six hundred twenty-one thousand, twenty-three".