646161 has 8 divisors (see below), whose sum is σ = 881760. Its totient is φ = 420672.

The previous prime is 646159. The next prime is 646169. The reversal of 646161 is 161646.

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

It is not a de Polignac number, because 646161 - 2¹ = 646159 is a prime.

It is a Smith number, since the sum of its digits (24) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (646169) 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, 2376 + ... + 2633.

It is an arithmetic number, because the mean of its divisors is an integer number (110220).

2⁶⁴⁶¹⁶¹ is an apocalyptic number.

It is an amenable number.

646161 is a deficient number, since it is larger than the sum of its proper divisors (235599).

646161 is a wasteful number, since it uses less digits than its factorization.

646161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5055.

The product of its digits is 864, while the sum is 24.

The square root of 646161 is about 803.8414022679. The cubic root of 646161 is about 86.4530356393.

The spelling of 646161 in words is "six hundred forty-six thousand, one hundred sixty-one".