81243519244 has 12 divisors (see below), whose sum is σ = 142212464800. Its totient is φ = 40611386448.

The previous prime is 81243519241. The next prime is 81243519263. The reversal of 81243519244 is 44291534218.

It is a self number, because there is not a number n which added to its sum of digits gives 81243519244.

It is not an unprimeable number, because it can be changed into a prime (81243519241) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2575659 + ... + 2607010.

Almost surely, 2^81243519244 is an apocalyptic number.

It is an amenable number.

81243519244 is a deficient number, since it is larger than the sum of its proper divisors (60968945556).

81243519244 is a wasteful number, since it uses less digits than its factorization.

81243519244 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5186592 (or 5186590 counting only the distinct ones).

The product of its digits is 276480, while the sum is 43.

The spelling of 81243519244 in words is "eighty-one billion, two hundred forty-three million, five hundred nineteen thousand, two hundred forty-four".