686665223 has 2 divisors, whose sum is σ = 686665224. Its totient is φ = 686665222.

The previous prime is 686665183. The next prime is 686665261. The reversal of 686665223 is 322566686.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-686665223 is a prime.

It is a super-3 number, since 3×686665223³ (a number of 27 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (686665123) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343332611 + 343332612.

It is an arithmetic number, because the mean of its divisors is an integer number (343332612).

Almost surely, 2^686665223 is an apocalyptic number.

686665223 is a deficient number, since it is larger than the sum of its proper divisors (1).

686665223 is an equidigital number, since it uses as much as digits as its factorization.

686665223 is an evil number, because the sum of its binary digits is even.

The product of its digits is 622080, while the sum is 44.

The square root of 686665223 is about 26204.2977963539. The cubic root of 686665223 is about 882.2297205359.

The spelling of 686665223 in words is "six hundred eighty-six million, six hundred sixty-five thousand, two hundred twenty-three".