81238806874 has 16 divisors (see below), whose sum is σ = 130257771840. Its totient is φ = 37905699040.

The previous prime is 81238806821. The next prime is 81238806889. The reversal of 81238806874 is 47860883218.

It is a super-2 number, since 2×81238806874² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21535444 + ... + 21539215.

It is an arithmetic number, because the mean of its divisors is an integer number (8141110740).

Almost surely, 2^81238806874 is an apocalyptic number.

81238806874 is a deficient number, since it is larger than the sum of its proper divisors (49018964966).

81238806874 is a wasteful number, since it uses less digits than its factorization.

81238806874 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43074725.

The product of its (nonzero) digits is 4128768, while the sum is 55.

The spelling of 81238806874 in words is "eighty-one billion, two hundred thirty-eight million, eight hundred six thousand, eight hundred seventy-four".