21111011100187 has 2 divisors, whose sum is σ = 21111011100188. Its totient is φ = 21111011100186.

The previous prime is 21111011100173. The next prime is 21111011100229. The reversal of 21111011100187 is 78100111011112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21111011100187 - 2¹¹ = 21111011098139 is a prime.

It is not a weakly prime, because it can be changed into another prime (21111011100107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555505550093 + 10555505550094.

It is an arithmetic number, because the mean of its divisors is an integer number (10555505550094).

Almost surely, 2^{21111011100187} is an apocalyptic number.

21111011100187 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111011100187 is an equidigital number, since it uses as much as digits as its factorization.

21111011100187 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 112, while the sum is 25.

Adding to 21111011100187 its reverse (78100111011112), we get a palindrome (99211122111299).

The spelling of 21111011100187 in words is "twenty-one trillion, one hundred eleven billion, eleven million, one hundred thousand, one hundred eighty-seven".