687909140 has 12 divisors (see below), whose sum is σ = 1444609236. Its totient is φ = 275163648.

The previous prime is 687909133. The next prime is 687909161. The reversal of 687909140 is 41909786.

It can be written as a sum of positive squares in 2 ways, for example, as 248503696 + 439405444 = 15764^2 + 20962^2 .

It is a junction number, because it is equal to n+sod(n) for n = 687909091 and 687909100.

It is a congruent number.

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, 17197709 + ... + 17197748.

It is an arithmetic number, because the mean of its divisors is an integer number (120384103).

Almost surely, 2^687909140 is an apocalyptic number.

It is an amenable number.

687909140 is an abundant number, since it is smaller than the sum of its proper divisors (756700096).

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

687909140 is a wasteful number, since it uses less digits than its factorization.

687909140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34395466 (or 34395464 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 44.

The square root of 687909140 is about 26228.0220375079. The cubic root of 687909140 is about 882.7621287145.

The spelling of 687909140 in words is "six hundred eighty-seven million, nine hundred nine thousand, one hundred forty".