1668403550669 has 2 divisors, whose sum is σ = 1668403550670. Its totient is φ = 1668403550668.

The previous prime is 1668403550647. The next prime is 1668403550731. The reversal of 1668403550669 is 9660553048661.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1300142696644 + 368260854025 = 1140238^2 + 606845^2 .

It is a cyclic number.

It is not a de Polignac number, because 1668403550669 - 2³² = 1664108583373 is a prime.

It is a super-2 number, since 2×1668403550669² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1668403550069) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 834201775334 + 834201775335.

It is an arithmetic number, because the mean of its divisors is an integer number (834201775335).

Almost surely, 2^{1668403550669} is an apocalyptic number.

It is an amenable number.

1668403550669 is a deficient number, since it is larger than the sum of its proper divisors (1).

1668403550669 is an equidigital number, since it uses as much as digits as its factorization.

1668403550669 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27993600, while the sum is 59.

The spelling of 1668403550669 in words is "one trillion, six hundred sixty-eight billion, four hundred three million, five hundred fifty thousand, six hundred sixty-nine".