668161 has 8 divisors (see below), whose sum is σ = 728000. Its totient is φ = 609552.

The previous prime is 668159. The next prime is 668179. The reversal of 668161 is 161866.

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

It is a cyclic number.

It is not a de Polignac number, because 668161 - 2¹ = 668159 is a prime.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (668111) 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, 1090 + ... + 1588.

It is an arithmetic number, because the mean of its divisors is an integer number (91000).

2⁶⁶⁸¹⁶¹ is an apocalyptic number.

It is an amenable number.

668161 is a deficient number, since it is larger than the sum of its proper divisors (59839).

668161 is a wasteful number, since it uses less digits than its factorization.

668161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 615.

The product of its digits is 1728, while the sum is 28.

The square root of 668161 is about 817.4111572520. The cubic root of 668161 is about 87.4232687863.

The spelling of 668161 in words is "six hundred sixty-eight thousand, one hundred sixty-one".