81440876523 has 16 divisors (see below), whose sum is σ = 112351353120. Its totient is φ = 52412795904.

The previous prime is 81440876521. The next prime is 81440876597. The reversal of 81440876523 is 32567804418.

It is not a de Polignac number, because 81440876523 - 2¹ = 81440876521 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81440876521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 455265 + ... + 608397.

It is an arithmetic number, because the mean of its divisors is an integer number (7021959570).

Almost surely, 2^81440876523 is an apocalyptic number.

81440876523 is a deficient number, since it is larger than the sum of its proper divisors (30910476597).

81440876523 is a wasteful number, since it uses less digits than its factorization.

81440876523 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159278.

The product of its (nonzero) digits is 1290240, while the sum is 48.

The spelling of 81440876523 in words is "eighty-one billion, four hundred forty million, eight hundred seventy-six thousand, five hundred twenty-three".