819000081 has 6 divisors (see below), whose sum is σ = 1183000130. Its totient is φ = 546000048.

The previous prime is 819000053. The next prime is 819000089. The reversal of 819000081 is 180000918.

It can be written as a sum of positive squares in only one way, i.e., 519156225 + 299843856 = 22785^2 + 17316^2 .

It is not a de Polignac number, because 819000081 - 2⁷ = 818999953 is a prime.

It is a super-2 number, since 2×819000081² = 1341522265356013122, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (819000089) 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 5 ways as a sum of consecutive naturals, for example, 45499996 + ... + 45500013.

Almost surely, 2^819000081 is an apocalyptic number.

It is an amenable number.

819000081 is a deficient number, since it is larger than the sum of its proper divisors (364000049).

819000081 is a wasteful number, since it uses less digits than its factorization.

819000081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91000015 (or 91000012 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 27.

The square root of 819000081 is about 28618.1774576929. The cubic root of 819000081 is about 935.6095545795.

Adding to 819000081 its reverse (180000918), we get a palindrome (999000999).

The spelling of 819000081 in words is "eight hundred nineteen million, eighty-one", and thus it is an aban number.