665440167719 has 2 divisors, whose sum is σ = 665440167720. Its totient is φ = 665440167718.

The previous prime is 665440167701. The next prime is 665440167731. The reversal of 665440167719 is 917761044566.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 665440167719 - 2¹² = 665440163623 is a prime.

It is a super-2 number, since 2×665440167719² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (665440167019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332720083859 + 332720083860.

It is an arithmetic number, because the mean of its divisors is an integer number (332720083860).

Almost surely, 2^665440167719 is an apocalyptic number.

665440167719 is a deficient number, since it is larger than the sum of its proper divisors (1).

665440167719 is an equidigital number, since it uses as much as digits as its factorization.

665440167719 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7620480, while the sum is 56.

The spelling of 665440167719 in words is "six hundred sixty-five billion, four hundred forty million, one hundred sixty-seven thousand, seven hundred nineteen".