819161 has 4 divisors (see below), whose sum is σ = 936192. Its totient is φ = 702132.

The previous prime is 819157. The next prime is 819167. The reversal of 819161 is 161918.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 819161 - 2² = 819157 is a prime.

It is a Duffinian number.

It is a plaindrome in base 15.

It is a self number, because there is not a number n which added to its sum of digits gives 819161.

It is not an unprimeable number, because it can be changed into a prime (819167) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 58505 + ... + 58518.

It is an arithmetic number, because the mean of its divisors is an integer number (234048).

2⁸¹⁹¹⁶¹ is an apocalyptic number.

It is an amenable number.

819161 is a deficient number, since it is larger than the sum of its proper divisors (117031).

819161 is a wasteful number, since it uses less digits than its factorization.

819161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117030.

The product of its digits is 432, while the sum is 26.

The square root of 819161 is about 905.0751350026. The cubic root of 819161 is about 93.5670827465.

The spelling of 819161 in words is "eight hundred nineteen thousand, one hundred sixty-one".