81272776 has 48 divisors (see below), whose sum is σ = 168652800. Its totient is φ = 36683712.

The previous prime is 81272773. The next prime is 81272827. The reversal of 81272776 is 67727218.

It is not an unprimeable number, because it can be changed into a prime (81272771) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 62905 + ... + 64183.

It is an arithmetic number, because the mean of its divisors is an integer number (3513600).

Almost surely, 2^81272776 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81272776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (84326400).

81272776 is an abundant number, since it is smaller than the sum of its proper divisors (87380024).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81272776 is a wasteful number, since it uses less digits than its factorization.

81272776 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1358 (or 1341 counting only the distinct ones).

The product of its digits is 65856, while the sum is 40.

The square root of 81272776 is about 9015.1414853013. The cubic root of 81272776 is about 433.1600195805.

The spelling of 81272776 in words is "eighty-one million, two hundred seventy-two thousand, seven hundred seventy-six".