81119933 has 2 divisors, whose sum is σ = 81119934. Its totient is φ = 81119932.

The previous prime is 81119917. The next prime is 81119939. The reversal of 81119933 is 33991118.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 44662489 + 36457444 = 6683^2 + 6038^2 .

It is a cyclic number.

It is not a de Polignac number, because 81119933 - 2⁴ = 81119917 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 81119893 and 81119902.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81119939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40559966 + 40559967.

It is an arithmetic number, because the mean of its divisors is an integer number (40559967).

Almost surely, 2^81119933 is an apocalyptic number.

It is an amenable number.

81119933 is a deficient number, since it is larger than the sum of its proper divisors (1).

81119933 is an equidigital number, since it uses as much as digits as its factorization.

81119933 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5832, while the sum is 35.

The square root of 81119933 is about 9006.6604798893. The cubic root of 81119933 is about 432.8883130881. Note that the first 3 decimals are identical.

The spelling of 81119933 in words is "eighty-one million, one hundred nineteen thousand, nine hundred thirty-three".