646123161 has 16 divisors (see below), whose sum is σ = 895752000. Its totient is φ = 413773248.

The previous prime is 646123157. The next prime is 646123171. The reversal of 646123161 is 161321646.

It is not a de Polignac number, because 646123161 - 2² = 646123157 is a prime.

It is not an unprimeable number, because it can be changed into a prime (646123151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1711 + ... + 35988.

It is an arithmetic number, because the mean of its divisors is an integer number (55984500).

Almost surely, 2^646123161 is an apocalyptic number.

It is an amenable number.

646123161 is a deficient number, since it is larger than the sum of its proper divisors (249628839).

646123161 is a wasteful number, since it uses less digits than its factorization.

646123161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37928.

The product of its digits is 5184, while the sum is 30.

The square root of 646123161 is about 25418.9527911753. The cubic root of 646123161 is about 864.5134805152.

The spelling of 646123161 in words is "six hundred forty-six million, one hundred twenty-three thousand, one hundred sixty-one".