1209003605209 has 3 divisors (see below), whose sum is σ = 1209004704757. Its totient is φ = 1209002505662.

The previous prime is 1209003605203. The next prime is 1209003605231. The reversal of 1209003605209 is 9025063009021.

The square root of 1209003605209 is 1099547.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 1209003605209 - 2⁵ = 1209003605177 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1209003605203) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 549774 + ... + 1649320.

Almost surely, 2^{1209003605209} is an apocalyptic number.

1209003605209 is the 1099547-th square number.

1209003605209 is the 549774-th centered octagonal number.

It is an amenable number.

1209003605209 is a deficient number, since it is larger than the sum of its proper divisors (1099548).

1209003605209 is an frugal number, since it uses more digits than its factorization.

1209003605209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2199094 (or 1099547 counting only the distinct ones).

The product of its (nonzero) digits is 29160, while the sum is 37.

The spelling of 1209003605209 in words is "one trillion, two hundred nine billion, three million, six hundred five thousand, two hundred nine".