660815 has 8 divisors (see below), whose sum is σ = 799200. Its totient is φ = 524512.

The previous prime is 660811. The next prime is 660817. The reversal of 660815 is 518066.

660815 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 660815 - 2² = 660811 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660811) 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, 302 + ... + 1188.

It is an arithmetic number, because the mean of its divisors is an integer number (99900).

2⁶⁶⁰⁸¹⁵ is an apocalyptic number.

660815 is a deficient number, since it is larger than the sum of its proper divisors (138385).

660815 is a wasteful number, since it uses less digits than its factorization.

660815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1041.

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 660815 is about 812.9052835355. The cubic root of 660815 is about 87.1016998925.

The spelling of 660815 in words is "six hundred sixty thousand, eight hundred fifteen".