81208180877 has 16 divisors (see below), whose sum is σ = 86508912000. Its totient is φ = 76012784640.

The previous prime is 81208180873. The next prime is 81208180883. The reversal of 81208180877 is 77808180218.

It is a cyclic number.

It is not a de Polignac number, because 81208180877 - 2² = 81208180873 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81208180873) 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, 1067177 + ... + 1140737.

It is an arithmetic number, because the mean of its divisors is an integer number (5406807000).

Almost surely, 2^81208180877 is an apocalyptic number.

It is an amenable number.

81208180877 is a deficient number, since it is larger than the sum of its proper divisors (5300731123).

81208180877 is a wasteful number, since it uses less digits than its factorization.

81208180877 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74276.

The product of its (nonzero) digits is 401408, while the sum is 50.

The spelling of 81208180877 in words is "eighty-one billion, two hundred eight million, one hundred eighty thousand, eight hundred seventy-seven".