666043111 has 2 divisors, whose sum is σ = 666043112. Its totient is φ = 666043110.

The previous prime is 666043109. The next prime is 666043121. The reversal of 666043111 is 111340666.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 666043111 - 2¹ = 666043109 is a prime.

It is a super-2 number, since 2×666043111² = 887226851421116642, which contains 22 as substring.

Together with 666043109, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 666043111.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666043121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333021555 + 333021556.

It is an arithmetic number, because the mean of its divisors is an integer number (333021556).

Almost surely, 2^666043111 is an apocalyptic number.

666043111 is a deficient number, since it is larger than the sum of its proper divisors (1).

666043111 is an equidigital number, since it uses as much as digits as its factorization.

666043111 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 666043111 is about 25807.8110462705. The cubic root of 666043111 is about 873.3080167509.

Adding to 666043111 its reverse (111340666), we get a palindrome (777383777).

The spelling of 666043111 in words is "six hundred sixty-six million, forty-three thousand, one hundred eleven".