81116443 has 2 divisors, whose sum is σ = 81116444. Its totient is φ = 81116442.

The previous prime is 81116411. The next prime is 81116459. The reversal of 81116443 is 34461118.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81116443 - 2⁵ = 81116411 is a prime.

It is equal to p_4730914 and since 81116443 and 4730914 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (81716443) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40558221 + 40558222.

It is an arithmetic number, because the mean of its divisors is an integer number (40558222).

Almost surely, 2^81116443 is an apocalyptic number.

81116443 is a deficient number, since it is larger than the sum of its proper divisors (1).

81116443 is an equidigital number, since it uses as much as digits as its factorization.

81116443 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2304, while the sum is 28.

The square root of 81116443 is about 9006.4667322985. The cubic root of 81116443 is about 432.8821049884.

The spelling of 81116443 in words is "eighty-one million, one hundred sixteen thousand, four hundred forty-three".