1321218809 has 8 divisors (see below), whose sum is σ = 1357358688. Its totient is φ = 1285265440.

The previous prime is 1321218803. The next prime is 1321218883. The reversal of 1321218809 is 9088121231.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1321218809 - 2⁴ = 1321218793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1321218803) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32207 + ... + 60660.

It is an arithmetic number, because the mean of its divisors is an integer number (169669836).

Almost surely, 2^1321218809 is an apocalyptic number.

It is an amenable number.

1321218809 is a deficient number, since it is larger than the sum of its proper divisors (36139879).

1321218809 is an equidigital number, since it uses as much as digits as its factorization.

1321218809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93255.

The product of its (nonzero) digits is 6912, while the sum is 35.

The square root of 1321218809 is about 36348.5736859096. The cubic root of 1321218809 is about 1097.2988294338.

The spelling of 1321218809 in words is "one billion, three hundred twenty-one million, two hundred eighteen thousand, eight hundred nine".