3218220720 has 800 divisors, whose sum is σ = 13793117184. Its totient is φ = 684288000.

The previous prime is 3218220679. The next prime is 3218220721. The reversal of 3218220720 is 270228123.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (3218220721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 21312645 + ... + 21312795.

Almost surely, 2^3218220720 is an apocalyptic number.

3218220720 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3218220720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6896558592).

3218220720 is an abundant number, since it is smaller than the sum of its proper divisors (10574896464).

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

3218220720 is a wasteful number, since it uses less digits than its factorization.

3218220720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 223 (or 208 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 3218220720 is about 56729.3638250950. The cubic root of 3218220720 is about 1476.4042121175.

Adding to 3218220720 its reverse (270228123), we get a palindrome (3488448843).

The spelling of 3218220720 in words is "three billion, two hundred eighteen million, two hundred twenty thousand, seven hundred twenty".