42856209 has 24 divisors (see below), whose sum is σ = 70036512. Its totient is φ = 25971840.

The previous prime is 42856207. The next prime is 42856213. The reversal of 42856209 is 90265824.

It is a happy number.

42856209 is a `hidden beast` number, since 4 + 28 + 5 + 620 + 9 = 666.

It is not a de Polignac number, because 42856209 - 2¹ = 42856207 is a prime.

It is not an unprimeable number, because it can be changed into a prime (42856207) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5344 + ... + 10689.

It is an arithmetic number, because the mean of its divisors is an integer number (2918188).

Almost surely, 2^42856209 is an apocalyptic number.

It is an amenable number.

42856209 is a deficient number, since it is larger than the sum of its proper divisors (27180303).

42856209 is a wasteful number, since it uses less digits than its factorization.

42856209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16059 (or 16047 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 42856209 is about 6546.4653821738. The cubic root of 42856209 is about 349.9488605555.

The spelling of 42856209 in words is "forty-two million, eight hundred fifty-six thousand, two hundred nine".