21112211212187 has 2 divisors, whose sum is σ = 21112211212188. Its totient is φ = 21112211212186.

The previous prime is 21112211212159. The next prime is 21112211212231. The reversal of 21112211212187 is 78121211221112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21112211212187 - 2⁶ = 21112211212123 is a prime.

It is not a weakly prime, because it can be changed into another prime (21112211212387) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556105606093 + 10556105606094.

It is an arithmetic number, because the mean of its divisors is an integer number (10556105606094).

Almost surely, 2^{21112211212187} is an apocalyptic number.

21112211212187 is a deficient number, since it is larger than the sum of its proper divisors (1).

21112211212187 is an equidigital number, since it uses as much as digits as its factorization.

21112211212187 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1792, while the sum is 32.

Adding to 21112211212187 its reverse (78121211221112), we get a palindrome (99233422433299).

The spelling of 21112211212187 in words is "twenty-one trillion, one hundred twelve billion, two hundred eleven million, two hundred twelve thousand, one hundred eighty-seven".