21121121102020 has 12 divisors (see below), whose sum is σ = 44354354314284. Its totient is φ = 8448448440800.

The previous prime is 21121121101987. The next prime is 21121121102027. The reversal of 21121121102020 is 2020112112112.

It can be written as a sum of positive squares in 2 ways, for example, as 16727511045184 + 4393610056836 = 4089928^2 + 2096094^2 .

It is a super-2 number, since 2×21121121102020² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21121121101985 and 21121121102003.

It is not an unprimeable number, because it can be changed into a prime (21121121102027) 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, 528028027531 + ... + 528028027570.

It is an arithmetic number, because the mean of its divisors is an integer number (3696196192857).

Almost surely, 2^{21121121102020} is an apocalyptic number.

21121121102020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21121121102020 is an abundant number, since it is smaller than the sum of its proper divisors (23233233212264).

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

21121121102020 is a wasteful number, since it uses less digits than its factorization.

21121121102020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1056056055110 (or 1056056055108 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21121121102020 its reverse (2020112112112), we get a palindrome (23141233214132).

The spelling of 21121121102020 in words is "twenty-one trillion, one hundred twenty-one billion, one hundred twenty-one million, one hundred two thousand, twenty".