688978134 has 48 divisors (see below), whose sum is σ = 1610319984. Its totient is φ = 211636800.

The previous prime is 688978109. The next prime is 688978141. The reversal of 688978134 is 431879886.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 159564 + ... + 163824.

It is an arithmetic number, because the mean of its divisors is an integer number (33548333).

Almost surely, 2^688978134 is an apocalyptic number.

688978134 is an abundant number, since it is smaller than the sum of its proper divisors (921341850).

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

688978134 is a wasteful number, since it uses less digits than its factorization.

688978134 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4973 (or 4970 counting only the distinct ones).

The product of its digits is 2322432, while the sum is 54.

The square root of 688978134 is about 26248.3929793807. The cubic root of 688978134 is about 883.2191556548.

The spelling of 688978134 in words is "six hundred eighty-eight million, nine hundred seventy-eight thousand, one hundred thirty-four".