666158 has 8 divisors (see below), whose sum is σ = 1011528. Its totient is φ = 328984.

The previous prime is 666143. The next prime is 666167. The reversal of 666158 is 851666.

Added to its reverse (851666) it gives a square (1517824 = 1232²).

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

It is a plaindrome in base 14.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 666158.

It is an unprimeable number.

666158 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1841 + ... + 2172.

It is an arithmetic number, because the mean of its divisors is an integer number (126441).

2⁶⁶⁶¹⁵⁸ is an apocalyptic number.

666158 is a deficient number, since it is larger than the sum of its proper divisors (345370).

666158 is a wasteful number, since it uses less digits than its factorization.

666158 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4098.

The product of its digits is 8640, while the sum is 32.

The square root of 666158 is about 816.1850280420. The cubic root of 666158 is about 87.3358227573.

Adding to 666158 its reverse (851666), we get a square (1517824 = 1232²).

The spelling of 666158 in words is "six hundred sixty-six thousand, one hundred fifty-eight".