81996244 has 24 divisors (see below), whose sum is σ = 158096736. Its totient is φ = 36900000.

The previous prime is 81996221. The next prime is 81996283. The reversal of 81996244 is 44269918.

It is a self number, because there is not a number n which added to its sum of digits gives 81996244.

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 7 ways as a sum of consecutive naturals, for example, 4782 + ... + 13669.

It is an arithmetic number, because the mean of its divisors is an integer number (6587364).

Almost surely, 2^81996244 is an apocalyptic number.

It is an amenable number.

81996244 is a deficient number, since it is larger than the sum of its proper divisors (76100492).

81996244 is a wasteful number, since it uses less digits than its factorization.

81996244 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18567 (or 18565 counting only the distinct ones).

The product of its digits is 124416, while the sum is 43.

The square root of 81996244 is about 9055.1777453565. The cubic root of 81996244 is about 434.4415151941.

The spelling of 81996244 in words is "eighty-one million, nine hundred ninety-six thousand, two hundred forty-four".