81118011 has 16 divisors (see below), whose sum is σ = 122608640. Its totient is φ = 47291040.

The previous prime is 81118007. The next prime is 81118013. The reversal of 81118011 is 11081118.

It is a happy number.

It is not a de Polignac number, because 81118011 - 2² = 81118007 is a prime.

It is a super-2 number, since 2×81118011² = 13160263417192242, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81118013) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 53995 + ... + 55476.

It is an arithmetic number, because the mean of its divisors is an integer number (7663040).

Almost surely, 2^81118011 is an apocalyptic number.

81118011 is a deficient number, since it is larger than the sum of its proper divisors (41490629).

81118011 is a wasteful number, since it uses less digits than its factorization.

81118011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109506.

The product of its (nonzero) digits is 64, while the sum is 21.

The square root of 81118011 is about 9006.5537804423. The cubic root of 81118011 is about 432.8848942082.

Adding to 81118011 its reverse (11081118), we get a palindrome (92199129).

The spelling of 81118011 in words is "eighty-one million, one hundred eighteen thousand, eleven".