131666 has 8 divisors (see below), whose sum is σ = 202224. Its totient is φ = 64260.

The previous prime is 131641. The next prime is 131671. The reversal of 131666 is 666131.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 131666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 680 + ... + 851.

It is an arithmetic number, because the mean of its divisors is an integer number (25278).

2¹³¹⁶⁶⁶ is an apocalyptic number.

131666 is a deficient number, since it is larger than the sum of its proper divisors (70558).

131666 is a wasteful number, since it uses less digits than its factorization.

131666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1576.

The product of its digits is 648, while the sum is 23.

The square root of 131666 is about 362.8580989864. The cubic root of 131666 is about 50.8734527558.

Adding to 131666 its reverse (666131), we get a palindrome (797797).

It can be divided in two parts, 131 and 666, that added together give a palindrome (797).

The spelling of 131666 in words is "one hundred thirty-one thousand, six hundred sixty-six".