687187408 has 20 divisors (see below), whose sum is σ = 1332704260. Its totient is φ = 343263744.

The previous prime is 687187373. The next prime is 687187427. The reversal of 687187408 is 804781786.

687187408 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 512207424 + 174979984 = 22632^2 + 13228^2 .

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, 2985 + ... + 37192.

It is an arithmetic number, because the mean of its divisors is an integer number (66635213).

Almost surely, 2^687187408 is an apocalyptic number.

It is an amenable number.

687187408 is a deficient number, since it is larger than the sum of its proper divisors (645516852).

687187408 is a wasteful number, since it uses less digits than its factorization.

687187408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41254 (or 41248 counting only the distinct ones).

The product of its (nonzero) digits is 602112, while the sum is 49.

The square root of 687187408 is about 26214.2596309718. The cubic root of 687187408 is about 882.4532988686.

The spelling of 687187408 in words is "six hundred eighty-seven million, one hundred eighty-seven thousand, four hundred eight".