21110130121 has 2 divisors, whose sum is σ = 21110130122. Its totient is φ = 21110130120.

The previous prime is 21110130077. The next prime is 21110130131. The reversal of 21110130121 is 12103101112.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19596920121 + 1513210000 = 139989^2 + 38900^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21110130121 is a prime.

It is not a weakly prime, because it can be changed into another prime (21110130131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555065060 + 10555065061.

It is an arithmetic number, because the mean of its divisors is an integer number (10555065061).

Almost surely, 2^21110130121 is an apocalyptic number.

It is an amenable number.

21110130121 is a deficient number, since it is larger than the sum of its proper divisors (1).

21110130121 is an equidigital number, since it uses as much as digits as its factorization.

21110130121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12, while the sum is 13.

Adding to 21110130121 its reverse (12103101112), we get a palindrome (33213231233).

The spelling of 21110130121 in words is "twenty-one billion, one hundred ten million, one hundred thirty thousand, one hundred twenty-one".