21211110122220 has 72 divisors (see below), whose sum is σ = 64340957758896. Its totient is φ = 5656244130432.

The previous prime is 21211110122117. The next prime is 21211110122317. The reversal of 21211110122220 is 2222101111212.

21211110122220 is a `hidden beast` number, since 2 + 1 + 211 + 110 + 122 + 220 = 666.

It is a super-2 number, since 2×21211110122220² (a number of 27 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 = 21211110122193 and 21211110122202.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 21654174 + ... + 22612506.

It is an arithmetic number, because the mean of its divisors is an integer number (893624413318).

Almost surely, 2^{21211110122220} is an apocalyptic number.

21211110122220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21211110122220 is an abundant number, since it is smaller than the sum of its proper divisors (43129847636676).

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

21211110122220 is a wasteful number, since it uses less digits than its factorization.

21211110122220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1081311 (or 1081306 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21211110122220 its reverse (2222101111212), we get a palindrome (23433211233432).

The spelling of 21211110122220 in words is "twenty-one trillion, two hundred eleven billion, one hundred ten million, one hundred twenty-two thousand, two hundred twenty".