118821909 has 4 divisors (see below), whose sum is σ = 158429216. Its totient is φ = 79214604.

The previous prime is 118821893. The next prime is 118821931. The reversal of 118821909 is 909128811.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 118821909 - 2⁴ = 118821893 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 (118821949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19803649 + ... + 19803654.

It is an arithmetic number, because the mean of its divisors is an integer number (39607304).

Almost surely, 2^118821909 is an apocalyptic number.

It is an amenable number.

118821909 is a deficient number, since it is larger than the sum of its proper divisors (39607307).

118821909 is an equidigital number, since it uses as much as digits as its factorization.

118821909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39607306.

The product of its (nonzero) digits is 10368, while the sum is 39.

The square root of 118821909 is about 10900.5462707151. The cubic root of 118821909 is about 491.6229802162.

The spelling of 118821909 in words is "one hundred eighteen million, eight hundred twenty-one thousand, nine hundred nine".