687672138 has 32 divisors (see below), whose sum is σ = 1406678400. Its totient is φ = 224035136.

The previous prime is 687672127. The next prime is 687672173. The reversal of 687672138 is 831276786.

687672138 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 81523 + ... + 89561.

It is an arithmetic number, because the mean of its divisors is an integer number (43958700).

Almost surely, 2^687672138 is an apocalyptic number.

687672138 is an abundant number, since it is smaller than the sum of its proper divisors (719006262).

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

687672138 is a wasteful number, since it uses less digits than its factorization.

687672138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8366.

The product of its digits is 677376, while the sum is 48.

The square root of 687672138 is about 26223.5035416704. The cubic root of 687672138 is about 882.6607391514.

The spelling of 687672138 in words is "six hundred eighty-seven million, six hundred seventy-two thousand, one hundred thirty-eight".