221966869 has 2 divisors, whose sum is σ = 221966870. Its totient is φ = 221966868.

The previous prime is 221966839. The next prime is 221966879. The reversal of 221966869 is 968669122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 145491844 + 76475025 = 12062^2 + 8745^2 .

It is a cyclic number.

It is not a de Polignac number, because 221966869 - 2¹³ = 221958677 is a prime.

It is a super-2 number, since 2×221966869² = 98538581867326322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221966819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110983434 + 110983435.

It is an arithmetic number, because the mean of its divisors is an integer number (110983435).

Almost surely, 2^221966869 is an apocalyptic number.

It is an amenable number.

221966869 is a deficient number, since it is larger than the sum of its proper divisors (1).

221966869 is an equidigital number, since it uses as much as digits as its factorization.

221966869 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 559872, while the sum is 49.

The square root of 221966869 is about 14898.5525807039. The cubic root of 221966869 is about 605.4747715570.

The spelling of 221966869 in words is "two hundred twenty-one million, nine hundred sixty-six thousand, eight hundred sixty-nine".