81515535059 has 16 divisors (see below), whose sum is σ = 97601120256. Its totient is φ = 66607358400.

The previous prime is 81515535047. The next prime is 81515535097. The reversal of 81515535059 is 95053551518.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81515535059 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81515535019) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2788802 + ... + 2817879.

It is an arithmetic number, because the mean of its divisors is an integer number (6100070016).

Almost surely, 2^81515535059 is an apocalyptic number.

81515535059 is a deficient number, since it is larger than the sum of its proper divisors (16085585197).

81515535059 is a wasteful number, since it uses less digits than its factorization.

81515535059 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5606786.

The product of its (nonzero) digits is 675000, while the sum is 47.

The spelling of 81515535059 in words is "eighty-one billion, five hundred fifteen million, five hundred thirty-five thousand, fifty-nine".