42002645 has 4 divisors (see below), whose sum is σ = 50403180. Its totient is φ = 33602112.

The previous prime is 42002629. The next prime is 42002647. The reversal of 42002645 is 54620024.

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 25020004 + 16982641 = 5002^2 + 4121^2 .

It is a cyclic number.

It is not a de Polignac number, because 42002645 - 2⁴ = 42002629 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 42002645.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42002647) 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 3 ways as a sum of consecutive naturals, for example, 4200260 + ... + 4200269.

It is an arithmetic number, because the mean of its divisors is an integer number (12600795).

Almost surely, 2^42002645 is an apocalyptic number.

It is an amenable number.

42002645 is a deficient number, since it is larger than the sum of its proper divisors (8400535).

42002645 is an equidigital number, since it uses as much as digits as its factorization.

42002645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8400534.

The product of its (nonzero) digits is 1920, while the sum is 23.

The square root of 42002645 is about 6480.9447613755. The cubic root of 42002645 is about 347.6099612327.

Adding to 42002645 its reverse (54620024), we get a palindrome (96622669).

The spelling of 42002645 in words is "forty-two million, two thousand, six hundred forty-five".