123212213209 has 4 divisors (see below), whose sum is σ = 123214279140. Its totient is φ = 123210147280.

The previous prime is 123212213191. The next prime is 123212213221. The reversal of 123212213209 is 902312212321.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 109116587584 + 14095625625 = 330328^2 + 118725^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-123212213209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (123212213239) 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 3 ways as a sum of consecutive naturals, for example, 940762 + ... + 1063699.

It is an arithmetic number, because the mean of its divisors is an integer number (30803569785).

Almost surely, 2^123212213209 is an apocalyptic number.

It is an amenable number.

123212213209 is a deficient number, since it is larger than the sum of its proper divisors (2065931).

123212213209 is an equidigital number, since it uses as much as digits as its factorization.

123212213209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2065930.

The product of its (nonzero) digits is 2592, while the sum is 28.

The spelling of 123212213209 in words is "one hundred twenty-three billion, two hundred twelve million, two hundred thirteen thousand, two hundred nine".