1686312169 has 2 divisors, whose sum is σ = 1686312170. Its totient is φ = 1686312168.

The previous prime is 1686312167. The next prime is 1686312193. The reversal of 1686312169 is 9612136861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1311308944 + 375003225 = 36212^2 + 19365^2 .

It is a cyclic number.

It is not a de Polignac number, because 1686312169 - 2¹ = 1686312167 is a prime.

It is a super-2 number, since 2×1686312169² = 5687297462634969122, which contains 22 as substring.

Together with 1686312167, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1686312167) by changing a digit.

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, 843156084 + 843156085.

It is an arithmetic number, because the mean of its divisors is an integer number (843156085).

Almost surely, 2^1686312169 is an apocalyptic number.

It is an amenable number.

1686312169 is a deficient number, since it is larger than the sum of its proper divisors (1).

1686312169 is an equidigital number, since it uses as much as digits as its factorization.

1686312169 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 93312, while the sum is 43.

The square root of 1686312169 is about 41064.7314492619. The cubic root of 1686312169 is about 1190.2713805661.

The spelling of 1686312169 in words is "one billion, six hundred eighty-six million, three hundred twelve thousand, one hundred sixty-nine".