685518432 has 24 divisors (see below), whose sum is σ = 1799486136. Its totient is φ = 228506112.

The previous prime is 685518403. The next prime is 685518439. The reversal of 685518432 is 234815586.

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-2 number, since 2×685518432² = 939871041223477248, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685518439) 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, 3570313 + ... + 3570504.

It is an arithmetic number, because the mean of its divisors is an integer number (74978589).

Almost surely, 2^685518432 is an apocalyptic number.

It is an amenable number.

685518432 is an abundant number, since it is smaller than the sum of its proper divisors (1113967704).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

685518432 is a wasteful number, since it uses less digits than its factorization.

685518432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7140830 (or 7140822 counting only the distinct ones).

The product of its digits is 230400, while the sum is 42.

The square root of 685518432 is about 26182.4069176231. The cubic root of 685518432 is about 881.7383132628.

The spelling of 685518432 in words is "six hundred eighty-five million, five hundred eighteen thousand, four hundred thirty-two".