18440666669 has 2 divisors, whose sum is σ = 18440666670. Its totient is φ = 18440666668.

The previous prime is 18440666633. The next prime is 18440666693. The reversal of 18440666669 is 96666604481.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9557604169 + 8883062500 = 97763^2 + 94250^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18440666669 is a prime.

It is a super-2 number, since 2×18440666669² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18440666609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9220333334 + 9220333335.

It is an arithmetic number, because the mean of its divisors is an integer number (9220333335).

Almost surely, 2^18440666669 is an apocalyptic number.

It is an amenable number.

18440666669 is a deficient number, since it is larger than the sum of its proper divisors (1).

18440666669 is an equidigital number, since it uses as much as digits as its factorization.

18440666669 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8957952, while the sum is 56.

The spelling of 18440666669 in words is "eighteen billion, four hundred forty million, six hundred sixty-six thousand, six hundred sixty-nine".