81537746120044 has 24 divisors (see below), whose sum is σ = 143237709892368. Its totient is φ = 40612859601600.

The previous prime is 81537746119997. The next prime is 81537746120141. The reversal of 81537746120044 is 44002164773518.

It is a junction number, because it is equal to n+sod(n) for n = 81537746119973 and 81537746120000.

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, 19800007 + ... + 23560894.

It is an arithmetic number, because the mean of its divisors is an integer number (5968237912182).

Almost surely, 2^{81537746120044} is an apocalyptic number.

It is an amenable number.

81537746120044 is a deficient number, since it is larger than the sum of its proper divisors (61699963772324).

81537746120044 is a wasteful number, since it uses less digits than its factorization.

81537746120044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43362705 (or 43362703 counting only the distinct ones).

The product of its (nonzero) digits is 4515840, while the sum is 52.

The spelling of 81537746120044 in words is "eighty-one trillion, five hundred thirty-seven billion, seven hundred forty-six million, one hundred twenty thousand, forty-four".