686378920 has 16 divisors (see below), whose sum is σ = 1544352660. Its totient is φ = 274551552.

The previous prime is 686378899. The next prime is 686378941. The reversal of 686378920 is 29873686.

686378920 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (686378899) and next prime (686378941).

It can be written as a sum of positive squares in 2 ways, for example, as 682985956 + 3392964 = 26134^2 + 1842^2 .

It is a super-2 number, since 2×686378920² = 942232043640732800, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8579697 + ... + 8579776.

Almost surely, 2^686378920 is an apocalyptic number.

It is an amenable number.

686378920 is an abundant number, since it is smaller than the sum of its proper divisors (857973740).

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

686378920 is a wasteful number, since it uses less digits than its factorization.

686378920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17159484 (or 17159480 counting only the distinct ones).

The product of its (nonzero) digits is 870912, while the sum is 49.

The square root of 686378920 is about 26198.8343252138. The cubic root of 686378920 is about 882.1070891476.

The spelling of 686378920 in words is "six hundred eighty-six million, three hundred seventy-eight thousand, nine hundred twenty".