21111100120247 has 2 divisors, whose sum is σ = 21111100120248. Its totient is φ = 21111100120246.

The previous prime is 21111100120213. The next prime is 21111100120273. The reversal of 21111100120247 is 74202100111112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21111100120247 - 2²² = 21111095925943 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21111102120247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555550060123 + 10555550060124.

It is an arithmetic number, because the mean of its divisors is an integer number (10555550060124).

Almost surely, 2^{21111100120247} is an apocalyptic number.

21111100120247 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111100120247 is an equidigital number, since it uses as much as digits as its factorization.

21111100120247 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 224, while the sum is 23.

Adding to 21111100120247 its reverse (74202100111112), we get a palindrome (95313200231359).

The spelling of 21111100120247 in words is "twenty-one trillion, one hundred eleven billion, one hundred million, one hundred twenty thousand, two hundred forty-seven".