81420326536 has 32 divisors (see below), whose sum is σ = 160739712000. Its totient is φ = 38557515456.

The previous prime is 81420326497. The next prime is 81420326549. The reversal of 81420326536 is 63562302418.

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, 535470 + ... + 670498.

It is an arithmetic number, because the mean of its divisors is an integer number (5023116000).

Almost surely, 2^81420326536 is an apocalyptic number.

It is an amenable number.

81420326536 is a deficient number, since it is larger than the sum of its proper divisors (79319385464).

81420326536 is a wasteful number, since it uses less digits than its factorization.

81420326536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139021 (or 139017 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 40.

The spelling of 81420326536 in words is "eighty-one billion, four hundred twenty million, three hundred twenty-six thousand, five hundred thirty-six".