686621320 has 96 divisors (see below), whose sum is σ = 1960562880. Its totient is φ = 214005120.

The previous prime is 686621317. The next prime is 686621357. The reversal of 686621320 is 23126686.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5637 + ... + 37483.

It is an arithmetic number, because the mean of its divisors is an integer number (20422530).

Almost surely, 2^686621320 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 686621320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (980281440).

686621320 is an abundant number, since it is smaller than the sum of its proper divisors (1273941560).

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

686621320 is a wasteful number, since it uses less digits than its factorization.

686621320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31883 (or 31872 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 34.

The square root of 686621320 is about 26203.4600768677. The cubic root of 686621320 is about 882.2109178959.

The spelling of 686621320 in words is "six hundred eighty-six million, six hundred twenty-one thousand, three hundred twenty".