81340806734 has 16 divisors (see below), whose sum is σ = 136700521776. Its totient is φ = 35973820800.

The previous prime is 81340806727. The next prime is 81340806739. The reversal of 81340806734 is 43760804318.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81340806739) by changing a digit.

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, 49962827 + ... + 49964454.

It is an arithmetic number, because the mean of its divisors is an integer number (8543782611).

Almost surely, 2^81340806734 is an apocalyptic number.

81340806734 is a deficient number, since it is larger than the sum of its proper divisors (55359715042).

81340806734 is a wasteful number, since it uses less digits than its factorization.

81340806734 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99927331.

The product of its (nonzero) digits is 387072, while the sum is 44.

The spelling of 81340806734 in words is "eighty-one billion, three hundred forty million, eight hundred six thousand, seven hundred thirty-four".