42171785 has 4 divisors (see below), whose sum is σ = 50606148. Its totient is φ = 33737424.

The previous prime is 42171769. The next prime is 42171791. The reversal of 42171785 is 58717124.

42171785 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in 2 ways, for example, as 5071504 + 37100281 = 2252^2 + 6091^2 .

It is a cyclic number.

It is not a de Polignac number, because 42171785 - 2⁴ = 42171769 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4217174 + ... + 4217183.

It is an arithmetic number, because the mean of its divisors is an integer number (12651537).

Almost surely, 2^42171785 is an apocalyptic number.

It is an amenable number.

42171785 is a deficient number, since it is larger than the sum of its proper divisors (8434363).

42171785 is an equidigital number, since it uses as much as digits as its factorization.

42171785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8434362.

The product of its digits is 15680, while the sum is 35.

The square root of 42171785 is about 6493.9806744400. The cubic root of 42171785 is about 348.0759319269.

The spelling of 42171785 in words is "forty-two million, one hundred seventy-one thousand, seven hundred eighty-five".