1221211171 has 2 divisors, whose sum is σ = 1221211172. Its totient is φ = 1221211170.

The previous prime is 1221211139. The next prime is 1221211177. The reversal of 1221211171 is 1711121221.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1221211171 - 2⁵ = 1221211139 is a prime.

It is not a weakly prime, because it can be changed into another prime (1221211177) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610605585 + 610605586.

It is an arithmetic number, because the mean of its divisors is an integer number (610605586).

Almost surely, 2^1221211171 is an apocalyptic number.

1221211171 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221211171 is an equidigital number, since it uses as much as digits as its factorization.

1221211171 is an evil number, because the sum of its binary digits is even.

The product of its digits is 56, while the sum is 19.

The square root of 1221211171 is about 34945.8319546123. The cubic root of 1221211171 is about 1068.8832121677.

Adding to 1221211171 its reverse (1711121221), we get a palindrome (2932332392).

The spelling of 1221211171 in words is "one billion, two hundred twenty-one million, two hundred eleven thousand, one hundred seventy-one".