1668704137 has 2 divisors, whose sum is σ = 1668704138. Its totient is φ = 1668704136.

The previous prime is 1668704131. The next prime is 1668704179. The reversal of 1668704137 is 7314078661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1422496656 + 246207481 = 37716^2 + 15691^2 .

It is a cyclic number.

It is not a de Polignac number, because 1668704137 - 2¹⁵ = 1668671369 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1668704093 and 1668704102.

It is not a weakly prime, because it can be changed into another prime (1668704131) 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, 834352068 + 834352069.

It is an arithmetic number, because the mean of its divisors is an integer number (834352069).

Almost surely, 2^1668704137 is an apocalyptic number.

It is an amenable number.

1668704137 is a deficient number, since it is larger than the sum of its proper divisors (1).

1668704137 is an equidigital number, since it uses as much as digits as its factorization.

1668704137 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 169344, while the sum is 43.

The square root of 1668704137 is about 40849.7752380598. The cubic root of 1668704137 is about 1186.1140423937.

The spelling of 1668704137 in words is "one billion, six hundred sixty-eight million, seven hundred four thousand, one hundred thirty-seven".