819441081 has 12 divisors (see below), whose sum is σ = 1224452580. Its totient is φ = 527456160.

The previous prime is 819441071. The next prime is 819441097. The reversal of 819441081 is 180144918.

819441081 is a `hidden beast` number, since 81 + 94 + 410 + 81 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 484880400 + 334560681 = 22020^2 + 18291^2 .

It is not a de Polignac number, because 819441081 - 2¹⁰ = 819440057 is a prime.

It is a super-2 number, since 2×819441081² = 1342967370460897122, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (819441041) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1569550 + ... + 1570071.

It is an arithmetic number, because the mean of its divisors is an integer number (102037715).

Almost surely, 2^819441081 is an apocalyptic number.

It is an amenable number.

819441081 is a deficient number, since it is larger than the sum of its proper divisors (405011499).

819441081 is a wasteful number, since it uses less digits than its factorization.

819441081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3139656 (or 3139653 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 36.

The square root of 819441081 is about 28625.8813139439. The cubic root of 819441081 is about 935.7774543507. Note that the first 3 decimals are identical.

Adding to 819441081 its reverse (180144918), we get a palindrome (999585999).

The spelling of 819441081 in words is "eight hundred nineteen million, four hundred forty-one thousand, eighty-one".