81944593815042 has 24 divisors (see below), whose sum is σ = 202910422780416. Its totient is φ = 23412741089976.

The previous prime is 81944593815041. The next prime is 81944593815059. The reversal of 81944593815042 is 24051839544918.

81944593815042 is a `hidden beast` number, since 8 + 1 + 9 + 4 + 45 + 9 + 3 + 81 + 504 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (81944593815041) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 325176959458 + ... + 325176959709.

It is an arithmetic number, because the mean of its divisors is an integer number (8454600949184).

Almost surely, 2^{81944593815042} is an apocalyptic number.

81944593815042 is an abundant number, since it is smaller than the sum of its proper divisors (120965828965374).

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

81944593815042 is a wasteful number, since it uses less digits than its factorization.

81944593815042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 650353919182 (or 650353919179 counting only the distinct ones).

The product of its (nonzero) digits is 49766400, while the sum is 63.

The spelling of 81944593815042 in words is "eighty-one trillion, nine hundred forty-four billion, five hundred ninety-three million, eight hundred fifteen thousand, forty-two".