42663865 has 4 divisors (see below), whose sum is σ = 51196644. Its totient is φ = 34131088.

The previous prime is 42663857. The next prime is 42663877. The reversal of 42663865 is 56836624.

It is a happy number.

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 10310521 + 32353344 = 3211^2 + 5688^2 .

It is a cyclic number.

It is not a de Polignac number, because 42663865 - 2³ = 42663857 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4266382 + ... + 4266391.

It is an arithmetic number, because the mean of its divisors is an integer number (12799161).

Almost surely, 2^42663865 is an apocalyptic number.

It is an amenable number.

42663865 is a deficient number, since it is larger than the sum of its proper divisors (8532779).

42663865 is an equidigital number, since it uses as much as digits as its factorization.

42663865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8532778.

The product of its digits is 207360, while the sum is 40.

The square root of 42663865 is about 6531.7581859711. The cubic root of 42663865 is about 349.4245373481.

The spelling of 42663865 in words is "forty-two million, six hundred sixty-three thousand, eight hundred sixty-five".