688170289 has 9 divisors (see below), whose sum is σ = 708271137. Its totient is φ = 668626704.

The previous prime is 688170247. The next prime is 688170337. The reversal of 688170289 is 982071886.

The square root of 688170289 is 26233.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 1311025 + 686859264 = 1145^2 + 26208^2 .

It is not a de Polignac number, because 688170289 - 2⁹ = 688169777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (688170229) 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 8 ways as a sum of consecutive naturals, for example, 970267 + ... + 970975.

It is an arithmetic number, because the mean of its divisors is an integer number (78696793).

Almost surely, 2^688170289 is an apocalyptic number.

688170289 is the 26233-rd square number.

688170289 is the 13117-th centered octagonal number.

It is an amenable number.

688170289 is a deficient number, since it is larger than the sum of its proper divisors (20100848).

688170289 is an frugal number, since it uses more digits than its factorization.

688170289 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1492 (or 746 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 49.

The cubic root of 688170289 is about 882.8738214114.

Multiplying 688170289 by its sum of digits (49), we get a square (33720344161 = 183631²).

The spelling of 688170289 in words is "six hundred eighty-eight million, one hundred seventy thousand, two hundred eighty-nine".