81049541513 has 16 divisors (see below), whose sum is σ = 88677371520. Its totient is φ = 73764815616.

The previous prime is 81049541491. The next prime is 81049541539. The reversal of 81049541513 is 31514594018.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81049541513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81049541543) 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 15 ways as a sum of consecutive naturals, for example, 292733 + ... + 497786.

It is an arithmetic number, because the mean of its divisors is an integer number (5542335720).

Almost surely, 2^81049541513 is an apocalyptic number.

It is an amenable number.

81049541513 is a deficient number, since it is larger than the sum of its proper divisors (7627830007).

81049541513 is a wasteful number, since it uses less digits than its factorization.

81049541513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 790736.

The product of its (nonzero) digits is 86400, while the sum is 41.

The spelling of 81049541513 in words is "eighty-one billion, forty-nine million, five hundred forty-one thousand, five hundred thirteen".