221211122220220 has 192 divisors, whose sum is σ = 539019141857280. Its totient is φ = 75463340268800.

The previous prime is 221211122220157. The next prime is 221211122220239. The reversal of 221211122220220 is 22022221112122.

221211122220220 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×221211122220220² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a junction number, because it is equal to n+sod(n) for n = 221211122220191 and 221211122220200.

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, 127811139 + ... + 129530341.

It is an arithmetic number, because the mean of its divisors is an integer number (2807391363840).

Almost surely, 2^{221211122220220} is an apocalyptic number.

221211122220220 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 221211122220220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (269509570928640).

221211122220220 is an abundant number, since it is smaller than the sum of its proper divisors (317808019637060).

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

221211122220220 is a wasteful number, since it uses less digits than its factorization.

221211122220220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1719736 (or 1719734 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 22.

Adding to 221211122220220 its reverse (22022221112122), we get a palindrome (243233343332342).

The spelling of 221211122220220 in words is "two hundred twenty-one trillion, two hundred eleven billion, one hundred twenty-two million, two hundred twenty thousand, two hundred twenty".