81076889 has 2 divisors, whose sum is σ = 81076890. Its totient is φ = 81076888.

The previous prime is 81076867. The next prime is 81076907. The reversal of 81076889 is 98867018.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 58675600 + 22401289 = 7660^2 + 4733^2 .

It is a cyclic number.

It is not a de Polignac number, because 81076889 - 2¹² = 81072793 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (81076829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40538444 + 40538445.

It is an arithmetic number, because the mean of its divisors is an integer number (40538445).

Almost surely, 2^81076889 is an apocalyptic number.

It is an amenable number.

81076889 is a deficient number, since it is larger than the sum of its proper divisors (1).

81076889 is an equidigital number, since it uses as much as digits as its factorization.

81076889 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 193536, while the sum is 47.

The square root of 81076889 is about 9004.2705978885. The cubic root of 81076889 is about 432.8117328915.

The spelling of 81076889 in words is "eighty-one million, seventy-six thousand, eight hundred eighty-nine".