1686745865 has 24 divisors (see below), whose sum is σ = 2493069192. Its totient is φ = 1088586240.

The previous prime is 1686745859. The next prime is 1686745873. The reversal of 1686745865 is 5685476861.

It can be written as a sum of positive squares in 4 ways, for example, as 826907536 + 859838329 = 28756^2 + 29323^2 .

It is not a de Polignac number, because 1686745865 - 2⁴ = 1686745849 is a prime.

It is a super-2 number, since 2×1686745865² = 5690223226189196450, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1686745865.

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 in 23 ways as a sum of consecutive naturals, for example, 198326 + ... + 206655.

It is an arithmetic number, because the mean of its divisors is an integer number (103877883).

Almost surely, 2^1686745865 is an apocalyptic number.

It is an amenable number.

1686745865 is a deficient number, since it is larger than the sum of its proper divisors (806323327).

1686745865 is a wasteful number, since it uses less digits than its factorization.

1686745865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 405017 (or 405010 counting only the distinct ones).

The product of its digits is 9676800, while the sum is 56.

The square root of 1686745865 is about 41070.0117482330. The cubic root of 1686745865 is about 1190.3734122258.

The spelling of 1686745865 in words is "one billion, six hundred eighty-six million, seven hundred forty-five thousand, eight hundred sixty-five".