81040404011 has 16 divisors (see below), whose sum is σ = 96951840768. Its totient is φ = 66275647200.

The previous prime is 81040404007. The next prime is 81040404043. The reversal of 81040404011 is 11040404018.

It is not a de Polignac number, because 81040404011 - 2² = 81040404007 is a prime.

It is a super-2 number, since 2×81040404011² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81040404091) 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, 2614580 + ... + 2645393.

It is an arithmetic number, because the mean of its divisors is an integer number (6059490048).

Almost surely, 2^81040404011 is an apocalyptic number.

81040404011 is a deficient number, since it is larger than the sum of its proper divisors (15911436757).

81040404011 is a wasteful number, since it uses less digits than its factorization.

81040404011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5260082.

The product of its (nonzero) digits is 512, while the sum is 23.

Adding to 81040404011 its reverse (11040404018), we get a palindrome (92080808029).

The spelling of 81040404011 in words is "eighty-one billion, forty million, four hundred four thousand, eleven".