42005645 has 8 divisors (see below), whose sum is σ = 54989280. Its totient is φ = 30549520.

The previous prime is 42005641. The next prime is 42005653. The reversal of 42005645 is 54650024.

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

It is not a de Polignac number, because 42005645 - 2² = 42005641 is a prime.

It is a super-3 number, since 3×42005645³ (a number of 24 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42005641) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 381815 + ... + 381924.

It is an arithmetic number, because the mean of its divisors is an integer number (6873660).

Almost surely, 2^42005645 is an apocalyptic number.

It is an amenable number.

42005645 is a deficient number, since it is larger than the sum of its proper divisors (12983635).

42005645 is a wasteful number, since it uses less digits than its factorization.

42005645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 763755.

The product of its (nonzero) digits is 4800, while the sum is 26.

The square root of 42005645 is about 6481.1762049801. The cubic root of 42005645 is about 347.6182369421.

Adding to 42005645 its reverse (54650024), we get a palindrome (96655669).

The spelling of 42005645 in words is "forty-two million, five thousand, six hundred forty-five".