211221022122 has 72 divisors (see below), whose sum is σ = 503847751680. Its totient is φ = 63902559600.

The previous prime is 211221022093. The next prime is 211221022139. The reversal of 211221022122 is 221220122112.

It is a happy number.

211221022122 is a `hidden beast` number, since 211 + 2 + 210 + 221 + 22 = 666.

It is a super-2 number, since 2×211221022122² (a number of 23 digits) contains 22 as substring.

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 = 211221022095 and 211221022104.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1269847 + ... + 1426517.

It is an arithmetic number, because the mean of its divisors is an integer number (6997885440).

Almost surely, 2^211221022122 is an apocalyptic number.

211221022122 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 211221022122, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (251923875840).

211221022122 is an abundant number, since it is smaller than the sum of its proper divisors (292626729558).

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

211221022122 is a wasteful number, since it uses less digits than its factorization.

211221022122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 157320 (or 157306 counting only the distinct ones).

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

Adding to 211221022122 its reverse (221220122112), we get a palindrome (432441144234).

The spelling of 211221022122 in words is "two hundred eleven billion, two hundred twenty-one million, twenty-two thousand, one hundred twenty-two".