661180 has 24 divisors (see below), whose sum is σ = 1495872. Its totient is φ = 244032.

The previous prime is 661139. The next prime is 661183. The reversal of 661180 is 81166.

661180 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 1012 + ... + 1531.

It is an arithmetic number, because the mean of its divisors is an integer number (62328).

2⁶⁶¹¹⁸⁰ is an apocalyptic number.

It is an amenable number.

661180 is an abundant number, since it is smaller than the sum of its proper divisors (834692).

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

661180 is a wasteful number, since it uses less digits than its factorization.

661180 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2565 (or 2563 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 22.

The square root of 661180 is about 813.1297559430. The cubic root of 661180 is about 87.1177337642.

It can be divided in two parts, 661 and 180, that added together give a square (841 = 29²).

The spelling of 661180 in words is "six hundred sixty-one thousand, one hundred eighty".