1685865853 has 4 divisors (see below), whose sum is σ = 1926703840. Its totient is φ = 1445027868.

The previous prime is 1685865851. The next prime is 1685865899. The reversal of 1685865853 is 3585685861.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 3585685861 = 2153 ⋅1665437.

It is a cyclic number.

It is not a de Polignac number, because 1685865853 - 2¹ = 1685865851 is a prime.

It is a super-2 number, since 2×1685865853² = 5684287348622835218, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1685865794 and 1685865803.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1685865851) 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 in 3 ways as a sum of consecutive naturals, for example, 120418983 + ... + 120418996.

It is an arithmetic number, because the mean of its divisors is an integer number (481675960).

Almost surely, 2^1685865853 is an apocalyptic number.

It is an amenable number.

1685865853 is a deficient number, since it is larger than the sum of its proper divisors (240837987).

1685865853 is an equidigital number, since it uses as much as digits as its factorization.

1685865853 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 240837986.

The product of its digits is 6912000, while the sum is 55.

The square root of 1685865853 is about 41059.2967913480. The cubic root of 1685865853 is about 1190.1663616485.

The spelling of 1685865853 in words is "one billion, six hundred eighty-five million, eight hundred sixty-five thousand, eight hundred fifty-three".