21020243111121 has 32 divisors (see below), whose sum is σ = 30255443804160. Its totient is φ = 12941391000384.

The previous prime is 21020243111099. The next prime is 21020243111177. The reversal of 21020243111121 is 12111134202012.

It is not a de Polignac number, because 21020243111121 - 2²⁶ = 21020176002257 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21020243111821) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 44392800 + ... + 44863806.

It is an arithmetic number, because the mean of its divisors is an integer number (945482618880).

Almost surely, 2^{21020243111121} is an apocalyptic number.

It is an amenable number.

21020243111121 is a deficient number, since it is larger than the sum of its proper divisors (9235200693039).

21020243111121 is a wasteful number, since it uses less digits than its factorization.

21020243111121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 493365.

The product of its (nonzero) digits is 192, while the sum is 21.

Adding to 21020243111121 its reverse (12111134202012), we get a palindrome (33131377313133).

The spelling of 21020243111121 in words is "twenty-one trillion, twenty billion, two hundred forty-three million, one hundred eleven thousand, one hundred twenty-one".