221142169 has 2 divisors, whose sum is σ = 221142170. Its totient is φ = 221142168.

The previous prime is 221142073. The next prime is 221142199. The reversal of 221142169 is 961241122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 209670400 + 11471769 = 14480^2 + 3387^2 .

It is a cyclic number.

It is not a de Polignac number, because 221142169 - 2⁷ = 221142041 is a prime.

It is a super-2 number, since 2×221142169² = 97807717820049122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (221142199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110571084 + 110571085.

It is an arithmetic number, because the mean of its divisors is an integer number (110571085).

Almost surely, 2^221142169 is an apocalyptic number.

It is an amenable number.

221142169 is a deficient number, since it is larger than the sum of its proper divisors (1).

221142169 is an equidigital number, since it uses as much as digits as its factorization.

221142169 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1728, while the sum is 28.

The square root of 221142169 is about 14870.8496394792. The cubic root of 221142169 is about 604.7239767213.

The spelling of 221142169 in words is "two hundred twenty-one million, one hundred forty-two thousand, one hundred sixty-nine".