6642220 has 48 divisors (see below), whose sum is σ = 15311520. Its totient is φ = 2405376.

The previous prime is 6642211. The next prime is 6642281. The reversal of 6642220 is 222466.

It is a happy number.

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 6642191 and 6642200.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 15124 + ... + 15556.

It is an arithmetic number, because the mean of its divisors is an integer number (318990).

Almost surely, 2^6642220 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6642220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7655760).

6642220 is an abundant number, since it is smaller than the sum of its proper divisors (8669300).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6642220 is a wasteful number, since it uses less digits than its factorization.

6642220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 514 (or 512 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 22.

The square root of 6642220 is about 2577.2504728877. The cubic root of 6642220 is about 187.9768720606.

Adding to 6642220 its reverse (222466), we get a palindrome (6864686).

The spelling of 6642220 in words is "six million, six hundred forty-two thousand, two hundred twenty".