20111211221020 has 48 divisors (see below), whose sum is σ = 42688761343200. Its totient is φ = 7958048587776.

The previous prime is 20111211221009. The next prime is 20111211221051. The reversal of 20111211221020 is 2012211211102.

It is a junction number, because it is equal to n+sod(n) for n = 20111211220985 and 20111211221003.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 7325445 + ... + 9689404.

It is an arithmetic number, because the mean of its divisors is an integer number (889349194650).

Almost surely, 2^{20111211221020} is an apocalyptic number.

20111211221020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20111211221020 is an abundant number, since it is smaller than the sum of its proper divisors (22577550122180).

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

20111211221020 is a wasteful number, since it uses less digits than its factorization.

20111211221020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17015494 (or 17015492 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 20111211221020 its reverse (2012211211102), we get a palindrome (22123422432122).

The spelling of 20111211221020 in words is "twenty trillion, one hundred eleven billion, two hundred eleven million, two hundred twenty-one thousand, twenty".