81855834 has 8 divisors (see below), whose sum is σ = 163711680. Its totient is φ = 27285276.

The previous prime is 81855817. The next prime is 81855859. The reversal of 81855834 is 43855818.

It is a sphenic number, since it is the product of 3 distinct primes.

81855834 is an admirable number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6821314 + ... + 6821325.

It is an arithmetic number, because the mean of its divisors is an integer number (20463960).

Almost surely, 2^81855834 is an apocalyptic number.

81855834 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81855834 is a wasteful number, since it uses less digits than its factorization.

81855834 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13642644.

The product of its digits is 153600, while the sum is 42.

The square root of 81855834 is about 9047.4214005981. The cubic root of 81855834 is about 434.1933949469.

The spelling of 81855834 in words is "eighty-one million, eight hundred fifty-five thousand, eight hundred thirty-four".