21122111122220 has 48 divisors (see below), whose sum is σ = 44546970686400. Its totient is φ = 8412610129920.

The previous prime is 21122111122169. The next prime is 21122111122237. The reversal of 21122111122220 is 2222111122112.

It is a super-2 number, since 2×21122111122220² (a number of 27 digits) contains 22 as substring.

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 = 21122111122192 and 21122111122201.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3950696 + ... + 7606064.

It is an arithmetic number, because the mean of its divisors is an integer number (928061889300).

Almost surely, 2^{21122111122220} is an apocalyptic number.

21122111122220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21122111122220 is an abundant number, since it is smaller than the sum of its proper divisors (23424859564180).

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

21122111122220 is a wasteful number, since it uses less digits than its factorization.

21122111122220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3656618 (or 3656616 counting only the distinct ones).

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

Adding to 21122111122220 its reverse (2222111122112), we get a palindrome (23344222244332).

The spelling of 21122111122220 in words is "twenty-one trillion, one hundred twenty-two billion, one hundred eleven million, one hundred twenty-two thousand, two hundred twenty".