81116811 has 6 divisors (see below), whose sum is σ = 117168740. Its totient is φ = 54077868.

The previous prime is 81116803. The next prime is 81116851. The reversal of 81116811 is 11861118.

It is not a de Polignac number, because 81116811 - 2³ = 81116803 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81116851) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4506481 + ... + 4506498.

Almost surely, 2^81116811 is an apocalyptic number.

81116811 is a deficient number, since it is larger than the sum of its proper divisors (36051929).

81116811 is a wasteful number, since it uses less digits than its factorization.

81116811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9012985 (or 9012982 counting only the distinct ones).

The product of its digits is 384, while the sum is 27.

The square root of 81116811 is about 9006.4871620405. The cubic root of 81116811 is about 432.8827596045.

Adding to 81116811 its reverse (11861118), we get a palindrome (92977929).

The spelling of 81116811 in words is "eighty-one million, one hundred sixteen thousand, eight hundred eleven".