21201120221020 has 12 divisors (see below), whose sum is σ = 44522352464184. Its totient is φ = 8480448088400.

The previous prime is 21201120220979. The next prime is 21201120221023. The reversal of 21201120221020 is 2012202110212.

It is a happy number.

It is a super-2 number, since 2×21201120221020² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21201120220985 and 21201120221003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21201120221023) 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, 530028005506 + ... + 530028005545.

It is an arithmetic number, because the mean of its divisors is an integer number (3710196038682).

Almost surely, 2^{21201120221020} is an apocalyptic number.

21201120221020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21201120221020 is an abundant number, since it is smaller than the sum of its proper divisors (23321232243164).

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

21201120221020 is a wasteful number, since it uses less digits than its factorization.

21201120221020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1060056011060 (or 1060056011058 counting only the distinct ones).

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

Adding to 21201120221020 its reverse (2012202110212), we get a palindrome (23213322331232).

The spelling of 21201120221020 in words is "twenty-one trillion, two hundred one billion, one hundred twenty million, two hundred twenty-one thousand, twenty".