81831244 has 24 divisors (see below), whose sum is σ = 160037136. Its totient is φ = 36288000.

The previous prime is 81831229. The next prime is 81831259. The reversal of 81831244 is 44213818.

It is an interprime number because it is at equal distance from previous prime (81831229) and next prime (81831259).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20877 + ... + 24484.

It is an arithmetic number, because the mean of its divisors is an integer number (6668214).

Almost surely, 2^81831244 is an apocalyptic number.

It is an amenable number.

81831244 is a deficient number, since it is larger than the sum of its proper divisors (78205892).

81831244 is a wasteful number, since it uses less digits than its factorization.

81831244 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45417 (or 45415 counting only the distinct ones).

The product of its digits is 6144, while the sum is 31.

The square root of 81831244 is about 9046.0623477843. The cubic root of 81831244 is about 434.1499124633.

The spelling of 81831244 in words is "eighty-one million, eight hundred thirty-one thousand, two hundred forty-four".