21120100120121 has 4 divisors (see below), whose sum is σ = 21569463952512. Its totient is φ = 20670736287732.

The previous prime is 21120100120039. The next prime is 21120100120201. The reversal of 21120100120121 is 12102100102112.

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 21120100120121 - 2¹⁴ = 21120100103737 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21120100120096 and 21120100120105.

It is not an unprimeable number, because it can be changed into a prime (21120100120921) 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, 224681916125 + ... + 224681916218.

It is an arithmetic number, because the mean of its divisors is an integer number (5392365988128).

Almost surely, 2^{21120100120121} is an apocalyptic number.

It is an amenable number.

21120100120121 is a deficient number, since it is larger than the sum of its proper divisors (449363832391).

21120100120121 is an equidigital number, since it uses as much as digits as its factorization.

21120100120121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 449363832390.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21120100120121 its reverse (12102100102112), we get a palindrome (33222200222233).

The spelling of 21120100120121 in words is "twenty-one trillion, one hundred twenty billion, one hundred million, one hundred twenty thousand, one hundred twenty-one".