81844843 has 2 divisors, whose sum is σ = 81844844. Its totient is φ = 81844842.

The previous prime is 81844801. The next prime is 81844849. The reversal of 81844843 is 34844818.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81844843 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81844796 and 81844805.

It is not a weakly prime, because it can be changed into another prime (81844849) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40922421 + 40922422.

It is an arithmetic number, because the mean of its divisors is an integer number (40922422).

Almost surely, 2^81844843 is an apocalyptic number.

81844843 is a deficient number, since it is larger than the sum of its proper divisors (1).

81844843 is an equidigital number, since it uses as much as digits as its factorization.

81844843 is an evil number, because the sum of its binary digits is even.

The product of its digits is 98304, while the sum is 40.

The square root of 81844843 is about 9046.8139695696. The cubic root of 81844843 is about 434.1739606441.

The spelling of 81844843 in words is "eighty-one million, eight hundred forty-four thousand, eight hundred forty-three".