20111121211020 has 192 divisors, whose sum is σ = 68433667900416. Its totient is φ = 4307857367040.

The previous prime is 20111121211009. The next prime is 20111121211021. The reversal of 20111121211020 is 2011212111102.

It is a happy number.

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

It is not an unprimeable number, because it can be changed into a prime (20111121211021) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4380766 + ... + 7708005.

It is an arithmetic number, because the mean of its divisors is an integer number (356425353648).

Almost surely, 2^{20111121211020} is an apocalyptic number.

20111121211020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20111121211020 is an abundant number, since it is smaller than the sum of its proper divisors (48322546689396).

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

20111121211020 is a wasteful number, since it uses less digits than its factorization.

20111121211020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12089040 (or 12089038 counting only the distinct ones).

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

Adding to 20111121211020 its reverse (2011212111102), we get a palindrome (22122333322122).

The spelling of 20111121211020 in words is "twenty trillion, one hundred eleven billion, one hundred twenty-one million, two hundred eleven thousand, twenty".