21212202020 has 24 divisors (see below), whose sum is σ = 44769480000. Its totient is φ = 8442241632.

The previous prime is 21212201963. The next prime is 21212202041. The reversal of 21212202020 is 2020221212.

It is a junction number, because it is equal to n+sod(n) for n = 21212201986 and 21212202004.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2660870 + ... + 2668829.

It is an arithmetic number, because the mean of its divisors is an integer number (1865395000).

Almost surely, 2^21212202020 is an apocalyptic number.

21212202020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21212202020 is an abundant number, since it is smaller than the sum of its proper divisors (23557277980).

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

21212202020 is a wasteful number, since it uses less digits than its factorization.

21212202020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5329907 (or 5329905 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 14.

Adding to 21212202020 its reverse (2020221212), we get a palindrome (23232423232).

The spelling of 21212202020 in words is "twenty-one billion, two hundred twelve million, two hundred two thousand, twenty".