81167885011 has 4 divisors (see below), whose sum is σ = 81168881224. Its totient is φ = 81166888800.

The previous prime is 81167885003. The next prime is 81167885021. The reversal of 81167885011 is 11058876118.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 11058876118 = 2 ⋅5529438059.

It is a cyclic number.

It is not a de Polignac number, because 81167885011 - 2³ = 81167885003 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81167885021) 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, 363825 + ... + 542866.

It is an arithmetic number, because the mean of its divisors is an integer number (20292220306).

Almost surely, 2^81167885011 is an apocalyptic number.

81167885011 is a deficient number, since it is larger than the sum of its proper divisors (996213).

81167885011 is an equidigital number, since it uses as much as digits as its factorization.

81167885011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 996212.

The product of its (nonzero) digits is 107520, while the sum is 46.

The spelling of 81167885011 in words is "eighty-one billion, one hundred sixty-seven million, eight hundred eighty-five thousand, eleven".