81539827003 has 4 divisors (see below), whose sum is σ = 82135008360. Its totient is φ = 80944645648.

The previous prime is 81539827001. The next prime is 81539827007. The reversal of 81539827003 is 30072893518.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 30072893518 = 2 ⋅15036446759.

It is a cyclic number.

It is not a de Polignac number, because 81539827003 - 2¹ = 81539827001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81539827001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 297590473 + ... + 297590746.

It is an arithmetic number, because the mean of its divisors is an integer number (20533752090).

Almost surely, 2^81539827003 is an apocalyptic number.

81539827003 is a deficient number, since it is larger than the sum of its proper divisors (595181357).

81539827003 is a wasteful number, since it uses less digits than its factorization.

81539827003 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 595181356.

The product of its (nonzero) digits is 362880, while the sum is 46.

The spelling of 81539827003 in words is "eighty-one billion, five hundred thirty-nine million, eight hundred twenty-seven thousand, three".