21122020111121 has 4 divisors (see below), whose sum is σ = 21251603056752. Its totient is φ = 20992437165492.

The previous prime is 21122020111081. The next prime is 21122020111123. The reversal of 21122020111121 is 12111102022112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21122020111121 - 2¹⁸ = 21122019848977 is a prime.

It is a super-2 number, since 2×21122020111121² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21122020111121.

It is not an unprimeable number, because it can be changed into a prime (21122020111123) 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, 64791472571 + ... + 64791472896.

It is an arithmetic number, because the mean of its divisors is an integer number (5312900764188).

Almost surely, 2^{21122020111121} is an apocalyptic number.

It is an amenable number.

21122020111121 is a deficient number, since it is larger than the sum of its proper divisors (129582945631).

21122020111121 is a wasteful number, since it uses less digits than its factorization.

21122020111121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129582945630.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21122020111121 its reverse (12111102022112), we get a palindrome (33233122133233).

The spelling of 21122020111121 in words is "twenty-one trillion, one hundred twenty-two billion, twenty million, one hundred eleven thousand, one hundred twenty-one".