688473621 has 16 divisors (see below), whose sum is σ = 1112685120. Its totient is φ = 417256560.

The previous prime is 688473619. The next prime is 688473647. The reversal of 688473621 is 126374886.

It is not a de Polignac number, because 688473621 - 2¹ = 688473619 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688473661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1158750 + ... + 1159343.

It is an arithmetic number, because the mean of its divisors is an integer number (69542820).

Almost surely, 2^688473621 is an apocalyptic number.

It is an amenable number.

688473621 is a deficient number, since it is larger than the sum of its proper divisors (424211499).

688473621 is a wasteful number, since it uses less digits than its factorization.

688473621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2318113 (or 2318107 counting only the distinct ones).

The product of its digits is 387072, while the sum is 45.

The square root of 688473621 is about 26238.7808596360. The cubic root of 688473621 is about 883.0035201930.

The spelling of 688473621 in words is "six hundred eighty-eight million, four hundred seventy-three thousand, six hundred twenty-one".