21201211022020 has 24 divisors (see below), whose sum is σ = 45022796443800. Its totient is φ = 8385198066432.

The previous prime is 21201211021997. The next prime is 21201211022111. The reversal of 21201211022020 is 2022011210212.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 103876864 + 21201107145156 = 10192^2 + 4604466^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21201211021985 and 21201211022003.

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, 5955394575 + ... + 5955398134.

It is an arithmetic number, because the mean of its divisors is an integer number (1875949851825).

Almost surely, 2^{21201211022020} is an apocalyptic number.

21201211022020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21201211022020 is an abundant number, since it is smaller than the sum of its proper divisors (23821585421780).

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

21201211022020 is a wasteful number, since it uses less digits than its factorization.

21201211022020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11910792807 (or 11910792805 counting only the distinct ones).

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

Adding to 21201211022020 its reverse (2022011210212), we get a palindrome (23223222232232).

The spelling of 21201211022020 in words is "twenty-one trillion, two hundred one billion, two hundred eleven million, twenty-two thousand, twenty".