108821209 has 8 divisors (see below), whose sum is σ = 126905600. Its totient is φ = 93275028.

The previous prime is 108821197. The next prime is 108821213. The reversal of 108821209 is 902128801.

It is a happy number.

It is not a de Polignac number, because 108821209 - 2¹⁹ = 108296921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (108821239) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 158289 + ... + 158974.

It is an arithmetic number, because the mean of its divisors is an integer number (15863200).

Almost surely, 2^108821209 is an apocalyptic number.

It is an amenable number.

108821209 is a deficient number, since it is larger than the sum of its proper divisors (18084391).

108821209 is an frugal number, since it uses more digits than its factorization.

108821209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 317284 (or 317270 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 31.

The square root of 108821209 is about 10431.7404588113. The cubic root of 108821209 is about 477.4242950803.

The spelling of 108821209 in words is "one hundred eight million, eight hundred twenty-one thousand, two hundred nine".