668536 has 32 divisors (see below), whose sum is σ = 1399680. Its totient is φ = 296800.

The previous prime is 668533. The next prime is 668539. The reversal of 668536 is 635866.

668536 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (668533) and next prime (668539).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668531) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6195 + ... + 6301.

It is an arithmetic number, because the mean of its divisors is an integer number (43740).

2⁶⁶⁸⁵³⁶ 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 668536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (699840).

668536 is an abundant number, since it is smaller than the sum of its proper divisors (731144).

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

668536 is a wasteful number, since it uses less digits than its factorization.

668536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195 (or 191 counting only the distinct ones).

The product of its digits is 25920, while the sum is 34.

The square root of 668536 is about 817.6405078028. The cubic root of 668536 is about 87.4396209303.

The spelling of 668536 in words is "six hundred sixty-eight thousand, five hundred thirty-six".