21030111021121 has 2 divisors, whose sum is σ = 21030111021122. Its totient is φ = 21030111021120.

The previous prime is 21030111021109. The next prime is 21030111021163. The reversal of 21030111021121 is 12112011103012.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20966654892096 + 63456129025 = 4578936^2 + 251905^2 .

It is a cyclic number.

It is not a de Polignac number, because 21030111021121 - 2⁵ = 21030111021089 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21030111021095 and 21030111021104.

It is not a weakly prime, because it can be changed into another prime (21030111021221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10515055510560 + 10515055510561.

It is an arithmetic number, because the mean of its divisors is an integer number (10515055510561).

Almost surely, 2^{21030111021121} is an apocalyptic number.

It is an amenable number.

21030111021121 is a deficient number, since it is larger than the sum of its proper divisors (1).

21030111021121 is an equidigital number, since it uses as much as digits as its factorization.

21030111021121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24, while the sum is 16.

Adding to 21030111021121 its reverse (12112011103012), we get a palindrome (33142122124133).

The spelling of 21030111021121 in words is "twenty-one trillion, thirty billion, one hundred eleven million, twenty-one thousand, one hundred twenty-one".