842909221 has 24 divisors (see below), whose sum is σ = 1116189504. Its totient is φ = 628246080.

The previous prime is 842909161. The next prime is 842909227. The reversal of 842909221 is 122909248.

842909221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 842909221 - 2¹⁷ = 842778149 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (842909227) 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, 21600 + ... + 46393.

It is an arithmetic number, because the mean of its divisors is an integer number (46507896).

Almost surely, 2^842909221 is an apocalyptic number.

It is an amenable number.

842909221 is a deficient number, since it is larger than the sum of its proper divisors (273280283).

842909221 is a wasteful number, since it uses less digits than its factorization.

842909221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68041 (or 68034 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 842909221 is about 29032.8989424067. The cubic root of 842909221 is about 944.6268119494.

The spelling of 842909221 in words is "eight hundred forty-two million, nine hundred nine thousand, two hundred twenty-one".