81579127895 has 4 divisors (see below), whose sum is σ = 97894953480. Its totient is φ = 65263302312.

The previous prime is 81579127891. The next prime is 81579127913. The reversal of 81579127895 is 59872197518.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81579127895 - 2² = 81579127891 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81579127891) 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, 8157912785 + ... + 8157912794.

It is an arithmetic number, because the mean of its divisors is an integer number (24473738370).

Almost surely, 2^81579127895 is an apocalyptic number.

81579127895 is a deficient number, since it is larger than the sum of its proper divisors (16315825585).

81579127895 is a wasteful number, since it uses less digits than its factorization.

81579127895 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16315825584.

The product of its digits is 12700800, while the sum is 62.

The spelling of 81579127895 in words is "eighty-one billion, five hundred seventy-nine million, one hundred twenty-seven thousand, eight hundred ninety-five".