81110881 has 4 divisors (see below), whose sum is σ = 81164992. Its totient is φ = 81056772.

The previous prime is 81110873. The next prime is 81110891. The reversal of 81110881 is 18801118.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81110881 - 2³ = 81110873 is a prime.

It is a super-2 number, since 2×81110881² = 13157950033192322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81110851) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24741 + ... + 27826.

It is an arithmetic number, because the mean of its divisors is an integer number (20291248).

Almost surely, 2^81110881 is an apocalyptic number.

It is an amenable number.

81110881 is a deficient number, since it is larger than the sum of its proper divisors (54111).

81110881 is a wasteful number, since it uses less digits than its factorization.

81110881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54110.

The product of its (nonzero) digits is 512, while the sum is 28.

The square root of 81110881 is about 9006.1579488703. The cubic root of 81110881 is about 432.8722107951.

Adding to 81110881 its reverse (18801118), we get a palindrome (99911999).

The spelling of 81110881 in words is "eighty-one million, one hundred ten thousand, eight hundred eighty-one".