21111121112047 has 2 divisors, whose sum is σ = 21111121112048. Its totient is φ = 21111121112046.

The previous prime is 21111121112021. The next prime is 21111121112087. The reversal of 21111121112047 is 74021112111112.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21111121112047 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21111121112087) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555560556023 + 10555560556024.

It is an arithmetic number, because the mean of its divisors is an integer number (10555560556024).

Almost surely, 2^{21111121112047} is an apocalyptic number.

21111121112047 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111121112047 is an equidigital number, since it uses as much as digits as its factorization.

21111121112047 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 224, while the sum is 25.

Adding to 21111121112047 its reverse (74021112111112), we get a palindrome (95132233223159).

The spelling of 21111121112047 in words is "twenty-one trillion, one hundred eleven billion, one hundred twenty-one million, one hundred twelve thousand, forty-seven".