687873321 has 24 divisors (see below), whose sum is σ = 1051415040. Its totient is φ = 432151200.

The previous prime is 687873317. The next prime is 687873323. The reversal of 687873321 is 123378786.

It is not a de Polignac number, because 687873321 - 2² = 687873317 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (687873323) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 22131 + ... + 43191.

It is an arithmetic number, because the mean of its divisors is an integer number (43808960).

Almost surely, 2^687873321 is an apocalyptic number.

It is an amenable number.

687873321 is a deficient number, since it is larger than the sum of its proper divisors (363541719).

687873321 is a wasteful number, since it uses less digits than its factorization.

687873321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21277 (or 21274 counting only the distinct ones).

The product of its digits is 338688, while the sum is 45.

The square root of 687873321 is about 26227.3391902419. The cubic root of 687873321 is about 882.7468068240.

The spelling of 687873321 in words is "six hundred eighty-seven million, eight hundred seventy-three thousand, three hundred twenty-one".