685863109 has 4 divisors (see below), whose sum is σ = 686248704. Its totient is φ = 685477516.

The previous prime is 685863107. The next prime is 685863163. The reversal of 685863109 is 901368586.

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.

It is a cyclic number.

It is not a de Polignac number, because 685863109 - 2¹ = 685863107 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685863107) 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 in 3 ways as a sum of consecutive naturals, for example, 190117 + ... + 193690.

It is an arithmetic number, because the mean of its divisors is an integer number (171562176).

Almost surely, 2^685863109 is an apocalyptic number.

It is an amenable number.

685863109 is a deficient number, since it is larger than the sum of its proper divisors (385595).

685863109 is a wasteful number, since it uses less digits than its factorization.

685863109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 385594.

The product of its (nonzero) digits is 311040, while the sum is 46.

The square root of 685863109 is about 26188.9883157025. The cubic root of 685863109 is about 881.8860671285.

The spelling of 685863109 in words is "six hundred eighty-five million, eight hundred sixty-three thousand, one hundred nine".