81281347 has 12 divisors (see below), whose sum is σ = 94957896. Its totient is φ = 69370560.

The previous prime is 81281327. The next prime is 81281357. The reversal of 81281347 is 74318218.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-81281347 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81281327) 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, 8368 + ... + 15250.

It is an arithmetic number, because the mean of its divisors is an integer number (7913158).

Almost surely, 2^81281347 is an apocalyptic number.

81281347 is a deficient number, since it is larger than the sum of its proper divisors (13676549).

81281347 is a wasteful number, since it uses less digits than its factorization.

81281347 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7138 (or 7131 counting only the distinct ones).

The product of its digits is 10752, while the sum is 34.

The square root of 81281347 is about 9015.6168396843. The cubic root of 81281347 is about 433.1752460159.

The spelling of 81281347 in words is "eighty-one million, two hundred eighty-one thousand, three hundred forty-seven".