221221121022 has 96 divisors (see below), whose sum is σ = 546169927680. Its totient is φ = 64096522560.

The previous prime is 221221120999. The next prime is 221221121117. The reversal of 221221121022 is 220121122122.

It is a happy number.

221221121022 is a `hidden beast` number, since 221 + 2 + 211 + 210 + 22 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 221221120986 and 221221121004.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 404403 + ... + 778449.

It is an arithmetic number, because the mean of its divisors is an integer number (5689270080).

Almost surely, 2^221221121022 is an apocalyptic number.

221221121022 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 221221121022, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (273084963840).

221221121022 is an abundant number, since it is smaller than the sum of its proper divisors (324948806658).

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

221221121022 is a wasteful number, since it uses less digits than its factorization.

221221121022 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 374198 (or 374195 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 221221121022 its reverse (220121122122), we get a palindrome (441342243144).

It can be divided in two parts, 221221 and 121022, that added together give a palindrome (342243).

The spelling of 221221121022 in words is "two hundred twenty-one billion, two hundred twenty-one million, one hundred twenty-one thousand, twenty-two".