81105042 has 8 divisors (see below), whose sum is σ = 162210096. Its totient is φ = 27035012.

The previous prime is 81105029. The next prime is 81105103. The reversal of 81105042 is 24050118.

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

81105042 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, 6758748 + ... + 6758759.

It is an arithmetic number, because the mean of its divisors is an integer number (20276262).

Almost surely, 2^81105042 is an apocalyptic number.

81105042 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.

81105042 is a wasteful number, since it uses less digits than its factorization.

81105042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13517512.

The product of its (nonzero) digits is 320, while the sum is 21.

The square root of 81105042 is about 9005.8337759477. The cubic root of 81105042 is about 432.8618233623.

The spelling of 81105042 in words is "eighty-one million, one hundred five thousand, forty-two".