660845 has 4 divisors (see below), whose sum is σ = 793020. Its totient is φ = 528672.

The previous prime is 660833. The next prime is 660851. The reversal of 660845 is 548066.

660845 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 548066 = 2 ⋅274033.

It can be written as a sum of positive squares in 2 ways, for example, as 498436 + 162409 = 706^2 + 403^2 .

It is a cyclic number.

It is not a de Polignac number, because 660845 - 2⁸ = 660589 is a prime.

It is a super-2 number, since 2×660845² = 873432228050, which contains 22 as substring.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 660845.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66080 + ... + 66089.

It is an arithmetic number, because the mean of its divisors is an integer number (198255).

2⁶⁶⁰⁸⁴⁵ is an apocalyptic number.

It is an amenable number.

660845 is a deficient number, since it is larger than the sum of its proper divisors (132175).

660845 is a wasteful number, since it uses less digits than its factorization.

660845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132174.

The product of its (nonzero) digits is 5760, while the sum is 29.

The square root of 660845 is about 812.9237356604. The cubic root of 660845 is about 87.1030179677.

The spelling of 660845 in words is "six hundred sixty thousand, eight hundred forty-five".