81444004502 has 64 divisors (see below), whose sum is σ = 146396712960. Its totient is φ = 33225233184.

The previous prime is 81444004489. The next prime is 81444004511. The reversal of 81444004502 is 20540044418.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 94812149 + ... + 94813007.

It is an arithmetic number, because the mean of its divisors is an integer number (2287448640).

Almost surely, 2^81444004502 is an apocalyptic number.

81444004502 is a deficient number, since it is larger than the sum of its proper divisors (64952708458).

81444004502 is a wasteful number, since it uses less digits than its factorization.

81444004502 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1977.

The product of its (nonzero) digits is 20480, while the sum is 32.

The spelling of 81444004502 in words is "eighty-one billion, four hundred forty-four million, four thousand, five hundred two".