81186567050013 has 4 divisors (see below), whose sum is σ = 108248756066688. Its totient is φ = 54124378033340.

The previous prime is 81186567049963. The next prime is 81186567050023. The reversal of 81186567050013 is 31005076568118.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81186567050013 - 2³³ = 81177977115421 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81186567050023) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13531094508333 + ... + 13531094508338.

It is an arithmetic number, because the mean of its divisors is an integer number (27062189016672).

Almost surely, 2^{81186567050013} is an apocalyptic number.

It is an amenable number.

81186567050013 is a deficient number, since it is larger than the sum of its proper divisors (27062189016675).

81186567050013 is a wasteful number, since it uses less digits than its factorization.

81186567050013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27062189016674.

The product of its (nonzero) digits is 1209600, while the sum is 51.

The spelling of 81186567050013 in words is "eighty-one trillion, one hundred eighty-six billion, five hundred sixty-seven million, fifty thousand, thirteen".