81489885867 has 32 divisors (see below), whose sum is σ = 130039963200. Its totient is φ = 50136973056.

The previous prime is 81489885833. The next prime is 81489885887. The reversal of 81489885867 is 76858898418.

81489885867 is a `hidden beast` number, since 8 + 1 + 489 + 8 + 85 + 8 + 67 = 666.

It is not a de Polignac number, because 81489885867 - 2¹¹ = 81489883819 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81489885795 and 81489885804.

It is not an unprimeable number, because it can be changed into a prime (81489885887) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1828809 + ... + 1872837.

It is an arithmetic number, because the mean of its divisors is an integer number (4063748850).

Almost surely, 2^81489885867 is an apocalyptic number.

81489885867 is a deficient number, since it is larger than the sum of its proper divisors (48550077333).

81489885867 is a wasteful number, since it uses less digits than its factorization.

81489885867 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49324 (or 49318 counting only the distinct ones).

The product of its digits is 247726080, while the sum is 72.

The spelling of 81489885867 in words is "eighty-one billion, four hundred eighty-nine million, eight hundred eighty-five thousand, eight hundred sixty-seven".