42509445 has 32 divisors (see below), whose sum is σ = 75613824. Its totient is φ = 20217600.

The previous prime is 42509443. The next prime is 42509459. The reversal of 42509445 is 54490524.

It is not a de Polignac number, because 42509445 - 2¹ = 42509443 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42509443) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6315 + ... + 11175.

It is an arithmetic number, because the mean of its divisors is an integer number (2362932).

Almost surely, 2^42509445 is an apocalyptic number.

It is an amenable number.

42509445 is a deficient number, since it is larger than the sum of its proper divisors (33104379).

42509445 is a wasteful number, since it uses less digits than its factorization.

42509445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4933.

The product of its (nonzero) digits is 28800, while the sum is 33.

The square root of 42509445 is about 6519.9267633924. The cubic root of 42509445 is about 349.0024520699.

Adding to 42509445 its reverse (54490524), we get a palindrome (96999969).

It can be divided in two parts, 4250 and 9445, that added together give a triangular number (13695 = T₁₆₅).

The spelling of 42509445 in words is "forty-two million, five hundred nine thousand, four hundred forty-five".