21013210220 has 12 divisors (see below), whose sum is σ = 44127741504. Its totient is φ = 8405284080.

The previous prime is 21013210157. The next prime is 21013210223. The reversal of 21013210220 is 2201231012.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21013210195 and 21013210204.

It is not an unprimeable number, because it can be changed into a prime (21013210223) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 525330236 + ... + 525330275.

It is an arithmetic number, because the mean of its divisors is an integer number (3677311792).

Almost surely, 2^21013210220 is an apocalyptic number.

21013210220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21013210220 is an abundant number, since it is smaller than the sum of its proper divisors (23114531284).

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

21013210220 is a wasteful number, since it uses less digits than its factorization.

21013210220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1050660520 (or 1050660518 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 14.

Adding to 21013210220 its reverse (2201231012), we get a palindrome (23214441232).

The spelling of 21013210220 in words is "twenty-one billion, thirteen million, two hundred ten thousand, two hundred twenty".