81528227 has 6 divisors (see below), whose sum is σ = 89613804. Its totient is φ = 74116460.

The previous prime is 81528217. The next prime is 81528229. The reversal of 81528227 is 72282518.

It is not a de Polignac number, because 81528227 - 2⁴ = 81528211 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81528229) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 336773 + ... + 337014.

It is an arithmetic number, because the mean of its divisors is an integer number (14935634).

Almost surely, 2^81528227 is an apocalyptic number.

81528227 is a deficient number, since it is larger than the sum of its proper divisors (8085577).

81528227 is a wasteful number, since it uses less digits than its factorization.

81528227 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 673809 (or 673798 counting only the distinct ones).

The product of its digits is 17920, while the sum is 35.

The square root of 81528227 is about 9029.2982562323. The cubic root of 81528227 is about 433.6133711915.

The spelling of 81528227 in words is "eighty-one million, five hundred twenty-eight thousand, two hundred twenty-seven".