21111021120 has 224 divisors, whose sum is σ = 76842372096. Its totient is φ = 4810291200.

The previous prime is 21111021101. The next prime is 21111021131. The reversal of 21111021120 is 2112011112.

It is a tau number, because it is divible by the number of its divisors (224).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 21111021096 and 21111021105.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2219575 + ... + 2229065.

It is an arithmetic number, because the mean of its divisors is an integer number (343046304).

Almost surely, 2^21111021120 is an apocalyptic number.

21111021120 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 21111021120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38421186048).

21111021120 is an abundant number, since it is smaller than the sum of its proper divisors (55731350976).

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

21111021120 is a wasteful number, since it uses less digits than its factorization.

21111021120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9849 (or 9839 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21111021120 its reverse (2112011112), we get a palindrome (23223032232).

The spelling of 21111021120 in words is "twenty-one billion, one hundred eleven million, twenty-one thousand, one hundred twenty".