1331209 has 4 divisors (see below), whose sum is σ = 1452240. Its totient is φ = 1210180.

The previous prime is 1331207. The next prime is 1331227. The reversal of 1331209 is 9021331.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1331209 - 2¹ = 1331207 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1331207) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 60499 + ... + 60520.

It is an arithmetic number, because the mean of its divisors is an integer number (363060).

2^1331209 is an apocalyptic number.

It is an amenable number.

1331209 is a deficient number, since it is larger than the sum of its proper divisors (121031).

1331209 is a wasteful number, since it uses less digits than its factorization.

1331209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121030.

The product of its (nonzero) digits is 162, while the sum is 19.

The square root of 1331209 is about 1153.7803083776. The cubic root of 1331209 is about 110.0057572744.

It can be divided in two parts, 1331 and 209, that added together give a triangular number (1540 = T₅₅).

The spelling of 1331209 in words is "one million, three hundred thirty-one thousand, two hundred nine".