81843424 has 24 divisors (see below), whose sum is σ = 173524680. Its totient is φ = 37773696.

The previous prime is 81843409. The next prime is 81843427. The reversal of 81843424 is 42434818.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 81843424.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81843427) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 97954 + ... + 98785.

It is an arithmetic number, because the mean of its divisors is an integer number (7230195).

Almost surely, 2^81843424 is an apocalyptic number.

It is an amenable number.

81843424 is an abundant number, since it is smaller than the sum of its proper divisors (91681256).

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

81843424 is a wasteful number, since it uses less digits than its factorization.

81843424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 196762 (or 196754 counting only the distinct ones).

The product of its digits is 24576, while the sum is 34.

The square root of 81843424 is about 9046.7355438302. The cubic root of 81843424 is about 434.1714514393.

The spelling of 81843424 in words is "eighty-one million, eight hundred forty-three thousand, four hundred twenty-four".