21111110221207 has 2 divisors, whose sum is σ = 21111110221208. Its totient is φ = 21111110221206.

The previous prime is 21111110221193. The next prime is 21111110221219. The reversal of 21111110221207 is 70212201111112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21111110221207 - 2¹⁵ = 21111110188439 is a prime.

It is a super-3 number, since 3×21111110221207³ (a number of 41 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21111110221297) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555555110603 + 10555555110604.

It is an arithmetic number, because the mean of its divisors is an integer number (10555555110604).

Almost surely, 2^{21111110221207} is an apocalyptic number.

21111110221207 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111110221207 is an equidigital number, since it uses as much as digits as its factorization.

21111110221207 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 22.

Adding to 21111110221207 its reverse (70212201111112), we get a palindrome (91323311332319).

The spelling of 21111110221207 in words is "twenty-one trillion, one hundred eleven billion, one hundred ten million, two hundred twenty-one thousand, two hundred seven".