690688 has 40 divisors (see below), whose sum is σ = 1473120. Its totient is φ = 322560.

The previous prime is 690673. The next prime is 690689. The reversal of 690688 is 886096.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (690689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9693 + ... + 9763.

It is an arithmetic number, because the mean of its divisors is an integer number (36828).

2⁶⁹⁰⁶⁸⁸ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 690688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (736560).

690688 is an abundant number, since it is smaller than the sum of its proper divisors (782432).

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

690688 is an equidigital number, since it uses as much as digits as its factorization.

690688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108 (or 92 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 690688 is about 831.0764104461. The cubic root of 690688 is about 88.3949192769.

It can be divided in two parts, 690 and 688, that added together give a triangular number (1378 = T₅₂).

The spelling of 690688 in words is "six hundred ninety thousand, six hundred eighty-eight".