81088700891 has 16 divisors (see below), whose sum is σ = 88949145600. Its totient is φ = 73310086080.

The previous prime is 81088700701. The next prime is 81088700941. The reversal of 81088700891 is 19800788018.

It is a de Polignac number, because none of the positive numbers 2^k-81088700891 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81088700591) 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, 5020070 + ... + 5036196.

It is an arithmetic number, because the mean of its divisors is an integer number (5559321600).

Almost surely, 2^81088700891 is an apocalyptic number.

81088700891 is a deficient number, since it is larger than the sum of its proper divisors (7860444709).

81088700891 is a wasteful number, since it uses less digits than its factorization.

81088700891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18634.

The product of its (nonzero) digits is 258048, while the sum is 50.

The spelling of 81088700891 in words is "eighty-one billion, eighty-eight million, seven hundred thousand, eight hundred ninety-one".