687621888 has 108 divisors (see below), whose sum is σ = 1996885800. Its totient is φ = 227555328.

The previous prime is 687621859. The next prime is 687621919. The reversal of 687621888 is 888126786.

687621888 is a `hidden beast` number, since 6 + 8 + 7 + 621 + 8 + 8 + 8 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 342295 + ... + 344297.

Almost surely, 2^687621888 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 687621888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (998442900).

687621888 is an abundant number, since it is smaller than the sum of its proper divisors (1309263912).

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

687621888 is a wasteful number, since it uses less digits than its factorization.

687621888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2174 (or 2157 counting only the distinct ones).

The product of its digits is 2064384, while the sum is 54.

The square root of 687621888 is about 26222.5454142042. The cubic root of 687621888 is about 882.6392391855.

The spelling of 687621888 in words is "six hundred eighty-seven million, six hundred twenty-one thousand, eight hundred eighty-eight".