221220232220 has 192 divisors, whose sum is σ = 521935142400. Its totient is φ = 78232780800.

The previous prime is 221220232217. The next prime is 221220232271. The reversal of 221220232220 is 22232022122.

It is a super-2 number, since 2×221220232220² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 221220232192 and 221220232201.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 210886256 + ... + 210887304.

It is an arithmetic number, because the mean of its divisors is an integer number (2718412200).

Almost surely, 2^221220232220 is an apocalyptic number.

221220232220 is a gapful number since it is divisible by the number (20) 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 221220232220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (260967571200).

221220232220 is an abundant number, since it is smaller than the sum of its proper divisors (300714910180).

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

221220232220 is a wasteful number, since it uses less digits than its factorization.

221220232220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1456 (or 1454 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 20.

Adding to 221220232220 its reverse (22232022122), we get a palindrome (243452254342).

It can be divided in two parts, 2212202 and 32220, that added together give a palindrome (2244422).

The spelling of 221220232220 in words is "two hundred twenty-one billion, two hundred twenty million, two hundred thirty-two thousand, two hundred twenty".