212345669 has 2 divisors, whose sum is σ = 212345670. Its totient is φ = 212345668.

The previous prime is 212345647. The next prime is 212345699. The reversal of 212345669 is 966543212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 177688900 + 34656769 = 13330^2 + 5887^2 .

It is a cyclic number.

It is not a de Polignac number, because 212345669 - 2¹² = 212341573 is a prime.

It is a super-2 number, since 2×212345669² = 90181366286115122, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212345699) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106172834 + 106172835.

It is an arithmetic number, because the mean of its divisors is an integer number (106172835).

Almost surely, 2^212345669 is an apocalyptic number.

It is an amenable number.

212345669 is a deficient number, since it is larger than the sum of its proper divisors (1).

212345669 is an equidigital number, since it uses as much as digits as its factorization.

212345669 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 77760, while the sum is 38.

The square root of 212345669 is about 14572.0852660146. The cubic root of 212345669 is about 596.5970970907.

The spelling of 212345669 in words is "two hundred twelve million, three hundred forty-five thousand, six hundred sixty-nine".