20111121211200 has 336 divisors, whose sum is σ = 68939347349376. Its totient is φ = 5123135283200.

The previous prime is 20111121211187. The next prime is 20111121211219. The reversal of 20111121211200 is 211212111102.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 20111121211200.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 85221370 + ... + 85457030.

It is an arithmetic number, because the mean of its divisors is an integer number (205176629016).

Almost surely, 2^{20111121211200} is an apocalyptic number.

20111121211200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20111121211200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34469673674688).

20111121211200 is an abundant number, since it is smaller than the sum of its proper divisors (48828226138176).

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

20111121211200 is a wasteful number, since it uses less digits than its factorization.

20111121211200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 236482 (or 236467 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 20111121211200 its reverse (211212111102), we get a palindrome (20322333322302).

The spelling of 20111121211200 in words is "twenty trillion, one hundred eleven billion, one hundred twenty-one million, two hundred eleven thousand, two hundred".