1668420746 has 4 divisors (see below), whose sum is σ = 2502631122. Its totient is φ = 834210372.

The previous prime is 1668420727. The next prime is 1668420751. The reversal of 1668420746 is 6470248661.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 1667497225 + 923521 = 40835^2 + 961^2 .

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1668420697 and 1668420706.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 417105185 + ... + 417105188.

Almost surely, 2^1668420746 is an apocalyptic number.

1668420746 is a deficient number, since it is larger than the sum of its proper divisors (834210376).

1668420746 is an equidigital number, since it uses as much as digits as its factorization.

1668420746 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 834210375.

The product of its (nonzero) digits is 387072, while the sum is 44.

The square root of 1668420746 is about 40846.3063936019. The cubic root of 1668420746 is about 1186.0468938666.

The spelling of 1668420746 in words is "one billion, six hundred sixty-eight million, four hundred twenty thousand, seven hundred forty-six".