21111310220 has 192 divisors, whose sum is σ = 59847524352. Its totient is φ = 6041088000.

The previous prime is 21111310201. The next prime is 21111310223. The reversal of 21111310220 is 2201311112.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a junction number, because it is equal to n+sod(n) for n = 21111310195 and 21111310204.

It is not an unprimeable number, because it can be changed into a prime (21111310223) 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, 3821060 + ... + 3826580.

It is an arithmetic number, because the mean of its divisors is an integer number (311705856).

Almost surely, 2^21111310220 is an apocalyptic number.

21111310220 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 21111310220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29923762176).

21111310220 is an abundant number, since it is smaller than the sum of its proper divisors (38736214132).

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

21111310220 is a wasteful number, since it uses less digits than its factorization.

21111310220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5752 (or 5750 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 14.

Adding to 21111310220 its reverse (2201311112), we get a palindrome (23312621332).

The spelling of 21111310220 in words is "twenty-one billion, one hundred eleven million, three hundred ten thousand, two hundred twenty".