1212321209 has 8 divisors (see below), whose sum is σ = 1324360128. Its totient is φ = 1100586960.

The previous prime is 1212321193. The next prime is 1212321233. The reversal of 1212321209 is 9021232121.

It is a happy number.

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

It is not a de Polignac number, because 1212321209 - 2⁴ = 1212321193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1212321109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 67802 + ... + 83795.

It is an arithmetic number, because the mean of its divisors is an integer number (165545016).

Almost surely, 2^1212321209 is an apocalyptic number.

It is an amenable number.

1212321209 is a deficient number, since it is larger than the sum of its proper divisors (112038919).

1212321209 is a wasteful number, since it uses less digits than its factorization.

1212321209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152335.

The product of its (nonzero) digits is 432, while the sum is 23.

The square root of 1212321209 is about 34818.4033091697. The cubic root of 1212321209 is about 1066.2832024724.

The spelling of 1212321209 in words is "one billion, two hundred twelve million, three hundred twenty-one thousand, two hundred nine".