442000209 has 8 divisors (see below), whose sum is σ = 673524160. Its totient is φ = 252571536.

The previous prime is 442000199. The next prime is 442000219. The reversal of 442000209 is 902000244.

It is an interprime number because it is at equal distance from previous prime (442000199) and next prime (442000219).

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

It is a de Polignac number, because none of the positive numbers 2^k-442000209 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21), and also a Moran number because the ratio is a prime number: 21047629 = 442000209 / (4 + 4 + 2 + 0 + 0 + 0 + 2 + 0 + 9).

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (442000219) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 10523794 + ... + 10523835.

It is an arithmetic number, because the mean of its divisors is an integer number (84190520).

Almost surely, 2^442000209 is an apocalyptic number.

It is an amenable number.

442000209 is a deficient number, since it is larger than the sum of its proper divisors (231523951).

442000209 is a wasteful number, since it uses less digits than its factorization.

442000209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21047639.

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 442000209 is about 21023.8010121862. The cubic root of 442000209 is about 761.7412803726.

The spelling of 442000209 in words is "four hundred forty-two million, two hundred nine", and thus it is an aban number.