1211221111187 has 2 divisors, whose sum is σ = 1211221111188. Its totient is φ = 1211221111186.

The previous prime is 1211221111181. The next prime is 1211221111193. The reversal of 1211221111187 is 7811111221121.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (1211221111181) and next prime (1211221111193).

It is a cyclic number.

It is not a de Polignac number, because 1211221111187 - 2⁴ = 1211221111171 is a prime.

It is not a weakly prime, because it can be changed into another prime (1211221111181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605610555593 + 605610555594.

It is an arithmetic number, because the mean of its divisors is an integer number (605610555594).

Almost surely, 2^{1211221111187} is an apocalyptic number.

1211221111187 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211221111187 is an equidigital number, since it uses as much as digits as its factorization.

1211221111187 is an evil number, because the sum of its binary digits is even.

The product of its digits is 448, while the sum is 29.

The spelling of 1211221111187 in words is "one trillion, two hundred eleven billion, two hundred twenty-one million, one hundred eleven thousand, one hundred eighty-seven".