81444370071004 has 24 divisors (see below), whose sum is σ = 142731902613888. Its totient is φ = 40663862623680.

The previous prime is 81444370070957. The next prime is 81444370071073. The reversal of 81444370071004 is 40017007344418.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4495422 + ... + 13531354.

It is an arithmetic number, because the mean of its divisors is an integer number (5947162608912).

Almost surely, 2^{81444370071004} is an apocalyptic number.

It is an amenable number.

81444370071004 is a deficient number, since it is larger than the sum of its proper divisors (61287532542884).

81444370071004 is a wasteful number, since it uses less digits than its factorization.

81444370071004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9039165 (or 9039163 counting only the distinct ones).

The product of its (nonzero) digits is 301056, while the sum is 43.

The spelling of 81444370071004 in words is "eighty-one trillion, four hundred forty-four billion, three hundred seventy million, seventy-one thousand, four".