818906161 has 8 divisors (see below), whose sum is σ = 839750184. Its totient is φ = 798103680.

The previous prime is 818906149. The next prime is 818906183. The reversal of 818906161 is 161609818.

It can be written as a sum of positive squares in 4 ways, for example, as 206640625 + 612265536 = 14375^2 + 24744^2 .

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 818906161 - 2⁹ = 818905649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (818906131) 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 7 ways as a sum of consecutive naturals, for example, 31675 + ... + 51391.

It is an arithmetic number, because the mean of its divisors is an integer number (104968773).

Almost surely, 2^818906161 is an apocalyptic number.

It is an amenable number.

818906161 is a deficient number, since it is larger than the sum of its proper divisors (20844023).

818906161 is a wasteful number, since it uses less digits than its factorization.

818906161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20771.

The product of its (nonzero) digits is 20736, while the sum is 40.

The square root of 818906161 is about 28616.5364955300. The cubic root of 818906161 is about 935.5737890932.

The spelling of 818906161 in words is "eight hundred eighteen million, nine hundred six thousand, one hundred sixty-one".