660765 has 48 divisors (see below), whose sum is σ = 1313280. Its totient is φ = 282240.

The previous prime is 660757. The next prime is 660769. The reversal of 660765 is 567066.

It is not a de Polignac number, because 660765 - 2³ = 660757 is a prime.

It is a super-2 number, since 2×660765² = 873220770450, which contains 22 as substring.

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

660765 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660769) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 21300 + ... + 21330.

It is an arithmetic number, because the mean of its divisors is an integer number (27360).

2⁶⁶⁰⁷⁶⁵ is an apocalyptic number.

It is an amenable number.

660765 is a deficient number, since it is larger than the sum of its proper divisors (652515).

660765 is a wasteful number, since it uses less digits than its factorization.

660765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82 (or 75 counting only the distinct ones).

The product of its (nonzero) digits is 7560, while the sum is 30.

The square root of 660765 is about 812.8745290634. The cubic root of 660765 is about 87.0995030120.

The spelling of 660765 in words is "six hundred sixty thousand, seven hundred sixty-five".