688716428 has 12 divisors (see below), whose sum is σ = 1214744832. Its totient is φ = 341646480.

The previous prime is 688716407. The next prime is 688716433. The reversal of 688716428 is 824617886.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 677363 + ... + 678378.

It is an arithmetic number, because the mean of its divisors is an integer number (101228736).

Almost surely, 2^688716428 is an apocalyptic number.

It is an amenable number.

688716428 is a deficient number, since it is larger than the sum of its proper divisors (526028404).

688716428 is a wasteful number, since it uses less digits than its factorization.

688716428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1355872 (or 1355870 counting only the distinct ones).

The product of its digits is 1032192, while the sum is 50.

The square root of 688716428 is about 26243.4073245072. The cubic root of 688716428 is about 883.1073122288.

The spelling of 688716428 in words is "six hundred eighty-eight million, seven hundred sixteen thousand, four hundred twenty-eight".