660618 has 48 divisors (see below), whose sum is σ = 1684800. Its totient is φ = 186984.

The previous prime is 660617. The next prime is 660619. The reversal of 660618 is 816066.

It is an interprime number because it is at equal distance from previous prime (660617) and next prime (660619).

It is a super-2 number, since 2×660618² = 872832283848, which contains 22 as substring.

It is a nialpdrome in base 7.

It is a junction number, because it is equal to n+sod(n) for n = 660591 and 660600.

It is not an unprimeable number, because it can be changed into a prime (660617) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6121 + ... + 6227.

It is an arithmetic number, because the mean of its divisors is an integer number (35100).

2⁶⁶⁰⁶¹⁸ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 660618, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (842400).

660618 is an abundant number, since it is smaller than the sum of its proper divisors (1024182).

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

660618 is a wasteful number, since it uses less digits than its factorization.

660618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136 (or 119 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 660618 is about 812.7841041753. The cubic root of 660618 is about 87.0930435413.

The spelling of 660618 in words is "six hundred sixty thousand, six hundred eighteen".