81839055487 has 8 divisors (see below), whose sum is σ = 93694730400. Its totient is φ = 70024475904.

The previous prime is 81839055449. The next prime is 81839055541. The reversal of 81839055487 is 78455093818.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81839055487 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81839055407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10269562 + ... + 10277527.

It is an arithmetic number, because the mean of its divisors is an integer number (11711841300).

Almost surely, 2^81839055487 is an apocalyptic number.

81839055487 is a deficient number, since it is larger than the sum of its proper divisors (11855674913).

81839055487 is a wasteful number, since it uses less digits than its factorization.

81839055487 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20547665.

The product of its (nonzero) digits is 9676800, while the sum is 58.

The spelling of 81839055487 in words is "eighty-one billion, eight hundred thirty-nine million, fifty-five thousand, four hundred eighty-seven".