981811 has 2 divisors, whose sum is σ = 981812. Its totient is φ = 981810.

The previous prime is 981809. The next prime is 981817. The reversal of 981811 is 118189.

It is a weak prime.

It is an emirp because it is prime and its reverse (118189) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 981811 - 2¹ = 981809 is a prime.

Together with 981809, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 981811.

It is not a weakly prime, because it can be changed into another prime (981817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 490905 + 490906.

It is an arithmetic number, because the mean of its divisors is an integer number (490906).

2⁹⁸¹⁸¹¹ is an apocalyptic number.

981811 is a deficient number, since it is larger than the sum of its proper divisors (1).

981811 is an equidigital number, since it uses as much as digits as its factorization.

981811 is an evil number, because the sum of its binary digits is even.

The product of its digits is 576, while the sum is 28.

The square root of 981811 is about 990.8637646014. The cubic root of 981811 is about 99.3899864006.

The spelling of 981811 in words is "nine hundred eighty-one thousand, eight hundred eleven".