21112141123421 has 2 divisors, whose sum is σ = 21112141123422. Its totient is φ = 21112141123420.

The previous prime is 21112141123393. The next prime is 21112141123427. The reversal of 21112141123421 is 12432114121112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12941610528025 + 8170530595396 = 3597445^2 + 2858414^2 .

It is a cyclic number.

It is not a de Polignac number, because 21112141123421 - 2⁴² = 16714094612317 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21112141123427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556070561710 + 10556070561711.

It is an arithmetic number, because the mean of its divisors is an integer number (10556070561711).

Almost surely, 2^{21112141123421} is an apocalyptic number.

It is an amenable number.

21112141123421 is a deficient number, since it is larger than the sum of its proper divisors (1).

21112141123421 is an equidigital number, since it uses as much as digits as its factorization.

21112141123421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 768, while the sum is 26.

Adding to 21112141123421 its reverse (12432114121112), we get a palindrome (33544255244533).

The spelling of 21112141123421 in words is "twenty-one trillion, one hundred twelve billion, one hundred forty-one million, one hundred twenty-three thousand, four hundred twenty-one".