842609209 has 16 divisors (see below), whose sum is σ = 968913792. Its totient is φ = 726663168.

The previous prime is 842609203. The next prime is 842609227. The reversal of 842609209 is 902906248.

It is a cyclic number.

It is not a de Polignac number, because 842609209 - 2²³ = 834220601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (842609203) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19912 + ... + 45625.

It is an arithmetic number, because the mean of its divisors is an integer number (60557112).

Almost surely, 2^842609209 is an apocalyptic number.

It is an amenable number.

842609209 is a deficient number, since it is larger than the sum of its proper divisors (126304583).

842609209 is a wasteful number, since it uses less digits than its factorization.

842609209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65616.

The product of its (nonzero) digits is 62208, while the sum is 40.

The square root of 842609209 is about 29027.7317233021. The cubic root of 842609209 is about 944.5147267246.

The spelling of 842609209 in words is "eight hundred forty-two million, six hundred nine thousand, two hundred nine".