221200101220 has 144 divisors (see below), whose sum is σ = 586102738032. Its totient is φ = 69637693440.

The previous prime is 221200101217. The next prime is 221200101257. The reversal of 221200101220 is 22101002122.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 1541033536 + 219659067684 = 39256^2 + 468678^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 221200101220.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 521142 + ... + 844978.

It is an arithmetic number, because the mean of its divisors is an integer number (4070157903).

Almost surely, 2^221200101220 is an apocalyptic number.

221200101220 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 221200101220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (293051369016).

221200101220 is an abundant number, since it is smaller than the sum of its proper divisors (364902636812).

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

221200101220 is a wasteful number, since it uses less digits than its factorization.

221200101220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 323918 (or 323909 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 221200101220 its reverse (22101002122), we get a palindrome (243301103342).

The spelling of 221200101220 in words is "two hundred twenty-one billion, two hundred million, one hundred one thousand, two hundred twenty".