685508823 has 6 divisors (see below), whose sum is σ = 990179424. Its totient is φ = 457005876.

The previous prime is 685508821. The next prime is 685508839. The reversal of 685508823 is 328805586.

It is a happy number.

685508823 is a `hidden beast` number, since 68 + 5 + 508 + 82 + 3 = 666.

It is not a de Polignac number, because 685508823 - 2¹ = 685508821 is a prime.

It is a super-4 number, since 4×685508823⁴ (a number of 36 digits) contains 4444 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685508821) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 38083815 + ... + 38083832.

It is an arithmetic number, because the mean of its divisors is an integer number (165029904).

Almost surely, 2^685508823 is an apocalyptic number.

685508823 is a deficient number, since it is larger than the sum of its proper divisors (304670601).

685508823 is a wasteful number, since it uses less digits than its factorization.

685508823 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76167653 (or 76167650 counting only the distinct ones).

The product of its (nonzero) digits is 460800, while the sum is 45.

The square root of 685508823 is about 26182.2234158980. The cubic root of 685508823 is about 881.7341934305.

The spelling of 685508823 in words is "six hundred eighty-five million, five hundred eight thousand, eight hundred twenty-three".