660858 has 64 divisors (see below), whose sum is σ = 1658880. Its totient is φ = 172800.

The previous prime is 660853. The next prime is 660887. The reversal of 660858 is 858066.

660858 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 660858.

It is not an unprimeable number, because it can be changed into a prime (660851) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 21303 + ... + 21333.

It is an arithmetic number, because the mean of its divisors is an integer number (25920).

2⁶⁶⁰⁸⁵⁸ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 660858, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (829440).

660858 is an abundant number, since it is smaller than the sum of its proper divisors (998022).

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

660858 is a wasteful number, since it uses less digits than its factorization.

660858 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83.

The product of its (nonzero) digits is 11520, while the sum is 33.

The square root of 660858 is about 812.9317314510. The cubic root of 660858 is about 87.1035891212.

It can be divided in two parts, 6608 and 58, that added together give a palindrome (6666).

The spelling of 660858 in words is "six hundred sixty thousand, eight hundred fifty-eight".