1021209 has 12 divisors (see below), whose sum is σ = 1584144. Its totient is φ = 583464.

The previous prime is 1021199. The next prime is 1021217. The reversal of 1021209 is 9021201.

It is a happy number.

It is not a de Polignac number, because 1021209 - 2⁷ = 1021081 is a prime.

It is a Curzon number.

1021209 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1021259) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3327 + ... + 3620.

It is an arithmetic number, because the mean of its divisors is an integer number (132012).

2^1021209 is an apocalyptic number.

It is an amenable number.

1021209 is a deficient number, since it is larger than the sum of its proper divisors (562935).

1021209 is an equidigital number, since it uses as much as digits as its factorization.

1021209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6964 (or 6957 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 15.

The square root of 1021209 is about 1010.5488607682. The cubic root of 1021209 is about 100.7020267186.

The spelling of 1021209 in words is "one million, twenty-one thousand, two hundred nine".