166440231 has 16 divisors (see below), whose sum is σ = 248524800. Its totient is φ = 110084184.

The previous prime is 166440199. The next prime is 166440233. The reversal of 166440231 is 132044661.

166440231 is a `hidden beast` number, since 16 + 644 + 0 + 2 + 3 + 1 = 666.

It is not a de Polignac number, because 166440231 - 2⁵ = 166440199 is a prime.

It is a super-2 number, since 2×166440231² = 55404700990666722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 166440195 and 166440204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166440233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20841 + ... + 27698.

It is an arithmetic number, because the mean of its divisors is an integer number (15532800).

Almost surely, 2^166440231 is an apocalyptic number.

166440231 is a deficient number, since it is larger than the sum of its proper divisors (82084569).

166440231 is a wasteful number, since it uses less digits than its factorization.

166440231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48675 (or 48669 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 166440231 is about 12901.1716909744. The cubic root of 166440231 is about 550.0718704978.

Adding to 166440231 its reverse (132044661), we get a palindrome (298484892).

The spelling of 166440231 in words is "one hundred sixty-six million, four hundred forty thousand, two hundred thirty-one".