21010221120 has 448 divisors, whose sum is σ = 81105670656. Its totient is φ = 4498391040.

The previous prime is 21010221073. The next prime is 21010221121. The reversal of 21010221120 is 2112201012.

It is a tau number, because it is divible by the number of its divisors (448).

It is a super-2 number, since 2×21010221120² (a number of 21 digits) contains 22 as substring.

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 = 21010221096 and 21010221105.

It is not an unprimeable number, because it can be changed into a prime (21010221121) 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, 40326460 + ... + 40326980.

Almost surely, 2^21010221120 is an apocalyptic number.

21010221120 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 21010221120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40552835328).

21010221120 is an abundant number, since it is smaller than the sum of its proper divisors (60095449536).

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

21010221120 is a wasteful number, since it uses less digits than its factorization.

21010221120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 918 (or 908 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21010221120 its reverse (2112201012), we get a palindrome (23122422132).

The spelling of 21010221120 in words is "twenty-one billion, ten million, two hundred twenty-one thousand, one hundred twenty".