81447282 has 96 divisors (see below), whose sum is σ = 212284800. Its totient is φ = 22923648.

The previous prime is 81447271. The next prime is 81447293. The reversal of 81447282 is 28274418.

It is an interprime number because it is at equal distance from previous prime (81447271) and next prime (81447293).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 302644 + ... + 302912.

It is an arithmetic number, because the mean of its divisors is an integer number (2211300).

Almost surely, 2^81447282 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81447282, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106142400).

81447282 is an abundant number, since it is smaller than the sum of its proper divisors (130837518).

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

81447282 is a wasteful number, since it uses less digits than its factorization.

81447282 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 382 (or 370 counting only the distinct ones).

The product of its digits is 28672, while the sum is 36.

The square root of 81447282 is about 9024.8147903433. The cubic root of 81447282 is about 433.4698198599.

The spelling of 81447282 in words is "eighty-one million, four hundred forty-seven thousand, two hundred eighty-two".