687317506 has 8 divisors (see below), whose sum is σ = 1031094540. Its totient is φ = 343619328.

The previous prime is 687317503. The next prime is 687317507. The reversal of 687317506 is 605713786.

It can be written as a sum of positive squares in 2 ways, for example, as 607376025 + 79941481 = 24645^2 + 8941^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (687317503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12810 + ... + 39226.

Almost surely, 2^687317506 is an apocalyptic number.

687317506 is a deficient number, since it is larger than the sum of its proper divisors (343777034).

687317506 is a wasteful number, since it uses less digits than its factorization.

687317506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39428.

The product of its (nonzero) digits is 211680, while the sum is 43.

The square root of 687317506 is about 26216.7409492484. The cubic root of 687317506 is about 882.5089839038.

The spelling of 687317506 in words is "six hundred eighty-seven million, three hundred seventeen thousand, five hundred six".