81728027277 has 8 divisors (see below), whose sum is σ = 117353064864. Its totient is φ = 50294170608.

The previous prime is 81728027267. The next prime is 81728027291. The reversal of 81728027277 is 77272082718.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 81728027277 - 2⁸ = 81728027021 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81728027257) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1047795183 + ... + 1047795260.

It is an arithmetic number, because the mean of its divisors is an integer number (14669133108).

Almost surely, 2^81728027277 is an apocalyptic number.

It is an amenable number.

81728027277 is a deficient number, since it is larger than the sum of its proper divisors (35625037587).

81728027277 is a wasteful number, since it uses less digits than its factorization.

81728027277 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2095590459.

The product of its (nonzero) digits is 1229312, while the sum is 51.

The spelling of 81728027277 in words is "eighty-one billion, seven hundred twenty-eight million, twenty-seven thousand, two hundred seventy-seven".