661230 has 64 divisors (see below), whose sum is σ = 1843200. Its totient is φ = 168480.

The previous prime is 661217. The next prime is 661231. The reversal of 661230 is 32166.

It is a happy number.

661230 is a `hidden beast` number, since 661 + 2 + 3 + 0 = 666.

It is a super-2 number, since 2×661230² = 874450225800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661231) by changing a digit.

661230 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8331 + ... + 8409.

It is an arithmetic number, because the mean of its divisors is an integer number (28800).

2⁶⁶¹²³⁰ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 661230, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (921600).

661230 is an abundant number, since it is smaller than the sum of its proper divisors (1181970).

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

661230 is a wasteful number, since it uses less digits than its factorization.

661230 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126 (or 120 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

The square root of 661230 is about 813.1605007623. The cubic root of 661230 is about 87.1199297254.

Adding to 661230 its reverse (32166), we get a palindrome (693396).

It can be divided in two parts, 66 and 1230, that added together give a 4-th power (1296 = 6⁴).

The spelling of 661230 in words is "six hundred sixty-one thousand, two hundred thirty".