688909158 has 128 divisors (see below), whose sum is σ = 1802787840. Its totient is φ = 190944000.

The previous prime is 688909157. The next prime is 688909171. The reversal of 688909158 is 851909886.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688909157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2744533 + ... + 2744783.

It is an arithmetic number, because the mean of its divisors is an integer number (14084280).

Almost surely, 2^688909158 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 688909158, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (901393920).

688909158 is an abundant number, since it is smaller than the sum of its proper divisors (1113878682).

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

688909158 is a wasteful number, since it uses less digits than its factorization.

688909158 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 459 (or 453 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 54.

The square root of 688909158 is about 26247.0790374853. The cubic root of 688909158 is about 883.1896806229.

The spelling of 688909158 in words is "six hundred eighty-eight million, nine hundred nine thousand, one hundred fifty-eight".