81528273 has 12 divisors (see below), whose sum is σ = 117907920. Its totient is φ = 54285336.

The previous prime is 81528263. The next prime is 81528283. The reversal of 81528273 is 37282518.

It is an interprime number because it is at equal distance from previous prime (81528263) and next prime (81528283).

It is not a de Polignac number, because 81528273 - 2⁵ = 81528241 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (81528203) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2818 + ... + 13076.

It is an arithmetic number, because the mean of its divisors is an integer number (9825660).

Almost surely, 2^81528273 is an apocalyptic number.

It is an amenable number.

81528273 is a deficient number, since it is larger than the sum of its proper divisors (36379647).

81528273 is a wasteful number, since it uses less digits than its factorization.

81528273 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11148 (or 11145 counting only the distinct ones).

The product of its digits is 26880, while the sum is 36.

The square root of 81528273 is about 9029.3008034953. The cubic root of 81528273 is about 433.6134527429.

The spelling of 81528273 in words is "eighty-one million, five hundred twenty-eight thousand, two hundred seventy-three".