819268081 has 4 divisors (see below), whose sum is σ = 819328500. Its totient is φ = 819207664.

The previous prime is 819268069. The next prime is 819268129. The reversal of 819268081 is 180862918.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 678133681 + 141134400 = 26041^2 + 11880^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-819268081 is a prime.

It is a super-2 number, since 2×819268081² = 1342400377090845122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (819268001) 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, 615 + ... + 40483.

It is an arithmetic number, because the mean of its divisors is an integer number (204832125).

It is a 13560-hyperperfect number.

Almost surely, 2^819268081 is an apocalyptic number.

It is an amenable number.

819268081 is a deficient number, since it is larger than the sum of its proper divisors (60419).

819268081 is a wasteful number, since it uses less digits than its factorization.

819268081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60418.

The product of its (nonzero) digits is 55296, while the sum is 43.

The square root of 819268081 is about 28622.8594134129. The cubic root of 819268081 is about 935.7115960897.

The spelling of 819268081 in words is "eight hundred nineteen million, two hundred sixty-eight thousand, eighty-one".