661185 has 24 divisors (see below), whose sum is σ = 1310400. Its totient is φ = 302112.

The previous prime is 661183. The next prime is 661187. The reversal of 661185 is 581166.

It is an interprime number because it is at equal distance from previous prime (661183) and next prime (661187).

It is not a de Polignac number, because 661185 - 2¹ = 661183 is a prime.

It is not an unprimeable number, because it can be changed into a prime (661183) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 735 + ... + 1364.

It is an arithmetic number, because the mean of its divisors is an integer number (54600).

2⁶⁶¹¹⁸⁵ is an apocalyptic number.

It is an amenable number.

661185 is a deficient number, since it is larger than the sum of its proper divisors (649215).

661185 is a wasteful number, since it uses less digits than its factorization.

661185 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2117 (or 2114 counting only the distinct ones).

The product of its digits is 1440, while the sum is 27.

The square root of 661185 is about 813.1328304773. The cubic root of 661185 is about 87.1179533653.

It can be divided in two parts, 66 and 1185, that multiplied together give a triangular number (78210 = T₃₉₅).

The spelling of 661185 in words is "six hundred sixty-one thousand, one hundred eighty-five".