81813411 has 12 divisors (see below), whose sum is σ = 124394920. Its totient is φ = 51671520.

The previous prime is 81813359. The next prime is 81813439. The reversal of 81813411 is 11431818.

It is not a de Polignac number, because 81813411 - 2⁷ = 81813283 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81823411) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 239050 + ... + 239391.

Almost surely, 2^81813411 is an apocalyptic number.

81813411 is a deficient number, since it is larger than the sum of its proper divisors (42581509).

81813411 is a wasteful number, since it uses less digits than its factorization.

81813411 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 478466 (or 478463 counting only the distinct ones).

The product of its digits is 768, while the sum is 27.

The square root of 81813411 is about 9045.0766165909. The cubic root of 81813411 is about 434.1183729295.

The spelling of 81813411 in words is "eighty-one million, eight hundred thirteen thousand, four hundred eleven".