21112121022021 has 16 divisors (see below), whose sum is σ = 31415001432000. Its totient is φ = 14012744051664.

The previous prime is 21112121022007. The next prime is 21112121022049. The reversal of 21112121022021 is 12022012121112.

21112121022021 is a `hidden beast` number, since 211 + 1 + 2 + 1 + 210 + 220 + 21 = 666.

It is not a de Polignac number, because 21112121022021 - 2⁵ = 21112121021989 is a prime.

It is a super-2 number, since 2×21112121022021² (a number of 27 digits) contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21112121021985 and 21112121022003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112121022221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1722307546 + ... + 1722319803.

It is an arithmetic number, because the mean of its divisors is an integer number (1963437589500).

Almost surely, 2^{21112121022021} is an apocalyptic number.

It is an amenable number.

21112121022021 is a deficient number, since it is larger than the sum of its proper divisors (10302880409979).

21112121022021 is a wasteful number, since it uses less digits than its factorization.

21112121022021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3444627585 (or 3444627579 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21112121022021 its reverse (12022012121112), we get a palindrome (33134133143133).

The spelling of 21112121022021 in words is "twenty-one trillion, one hundred twelve billion, one hundred twenty-one million, twenty-two thousand, twenty-one".