21121021002220 has 12 divisors (see below), whose sum is σ = 44354144104704. Its totient is φ = 8448408400880.

The previous prime is 21121021002217. The next prime is 21121021002253. The reversal of 21121021002220 is 2220012012112.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21121021002194 and 21121021002203.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 528025525036 + ... + 528025525075.

It is an arithmetic number, because the mean of its divisors is an integer number (3696178675392).

Almost surely, 2^{21121021002220} is an apocalyptic number.

21121021002220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21121021002220 is an abundant number, since it is smaller than the sum of its proper divisors (23233123102484).

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

21121021002220 is a wasteful number, since it uses less digits than its factorization.

21121021002220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1056051050120 (or 1056051050118 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21121021002220 its reverse (2220012012112), we get a palindrome (23341033014332).

The spelling of 21121021002220 in words is "twenty-one trillion, one hundred twenty-one billion, twenty-one million, two thousand, two hundred twenty".