1213209 has 12 divisors (see below), whose sum is σ = 1765296. Its totient is φ = 802872.

The previous prime is 1213189. The next prime is 1213213. The reversal of 1213209 is 9023121.

It is a happy number.

It is not a de Polignac number, because 1213209 - 2⁷ = 1213081 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1213191 and 1213200.

It is not an unprimeable number, because it can be changed into a prime (1213259) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1054 + ... + 1880.

It is an arithmetic number, because the mean of its divisors is an integer number (147108).

2^1213209 is an apocalyptic number.

It is an amenable number.

1213209 is a deficient number, since it is larger than the sum of its proper divisors (552087).

1213209 is a wasteful number, since it uses less digits than its factorization.

1213209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 996 (or 993 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

The square root of 1213209 is about 1101.4576705439. The cubic root of 1213209 is about 106.6543421090.

The spelling of 1213209 in words is "one million, two hundred thirteen thousand, two hundred nine".