81847238 has 32 divisors (see below), whose sum is σ = 138205440. Its totient is φ = 36036000.

The previous prime is 81847229. The next prime is 81847243. The reversal of 81847238 is 83274818.

It is a Smith number, since the sum of its digits (41) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 81847195 and 81847204.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 94853 + ... + 95711.

It is an arithmetic number, because the mean of its divisors is an integer number (4318920).

Almost surely, 2^81847238 is an apocalyptic number.

81847238 is a deficient number, since it is larger than the sum of its proper divisors (56358202).

81847238 is a wasteful number, since it uses less digits than its factorization.

81847238 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1004.

The product of its digits is 86016, while the sum is 41.

The square root of 81847238 is about 9046.9463356428. The cubic root of 81847238 is about 434.1781956349.

The spelling of 81847238 in words is "eighty-one million, eight hundred forty-seven thousand, two hundred thirty-eight".