21120120222121 has 4 divisors (see below), whose sum is σ = 21120184363392. Its totient is φ = 21120056080852.

The previous prime is 21120120222079. The next prime is 21120120222137. The reversal of 21120120222121 is 12122202102112.

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 21120120222121 - 2³⁹ = 20570364408233 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21120120222151) 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, 31574161 + ... + 32236126.

It is an arithmetic number, because the mean of its divisors is an integer number (5280046090848).

Almost surely, 2^{21120120222121} is an apocalyptic number.

It is an amenable number.

21120120222121 is a deficient number, since it is larger than the sum of its proper divisors (64141271).

21120120222121 is an equidigital number, since it uses as much as digits as its factorization.

21120120222121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64141270.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 21120120222121 its reverse (12122202102112), we get a palindrome (33242322324233).

The spelling of 21120120222121 in words is "twenty-one trillion, one hundred twenty billion, one hundred twenty million, two hundred twenty-two thousand, one hundred twenty-one".