221211221120120 has 256 divisors, whose sum is σ = 634154921164800. Its totient is φ = 67438150709760.

The previous prime is 221211221120119. The next prime is 221211221120129. The reversal of 221211221120120 is 21021122112122.

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 = 221211221120092 and 221211221120101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221211221120129) 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 63 ways as a sum of consecutive naturals, for example, 222869501 + ... + 223859859.

It is an arithmetic number, because the mean of its divisors is an integer number (2477167660800).

Almost surely, 2^{221211221120120} is an apocalyptic number.

221211221120120 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 221211221120120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (317077460582400).

221211221120120 is an abundant number, since it is smaller than the sum of its proper divisors (412943700044680).

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

221211221120120 is a wasteful number, since it uses less digits than its factorization.

221211221120120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 991978 (or 991974 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 221211221120120 its reverse (21021122112122), we get a palindrome (242232343232242).

The spelling of 221211221120120 in words is "two hundred twenty-one trillion, two hundred eleven billion, two hundred twenty-one million, one hundred twenty thousand, one hundred twenty".