81537573334 has 16 divisors (see below), whose sum is σ = 140065728768. Its totient is φ = 34872916392.

The previous prime is 81537573241. The next prime is 81537573347. The reversal of 81537573334 is 43337573518.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5972764 + ... + 5986399.

It is an arithmetic number, because the mean of its divisors is an integer number (8754108048).

Almost surely, 2^81537573334 is an apocalyptic number.

81537573334 is a deficient number, since it is larger than the sum of its proper divisors (58528155434).

81537573334 is a wasteful number, since it uses less digits than its factorization.

81537573334 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11959659.

The product of its digits is 3175200, while the sum is 49.

The spelling of 81537573334 in words is "eighty-one billion, five hundred thirty-seven million, five hundred seventy-three thousand, three hundred thirty-four".