1243409 has 4 divisors (see below), whose sum is σ = 1260516. Its totient is φ = 1226304.

The previous prime is 1243393. The next prime is 1243421. The reversal of 1243409 is 9043421.

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 483025 + 760384 = 695^2 + 872^2 .

It is a cyclic number.

It is not a de Polignac number, because 1243409 - 2⁴ = 1243393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1243439) 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, 8444 + ... + 8589.

It is an arithmetic number, because the mean of its divisors is an integer number (315129).

2^1243409 is an apocalyptic number.

It is an amenable number.

1243409 is a deficient number, since it is larger than the sum of its proper divisors (17107).

1243409 is an equidigital number, since it uses as much as digits as its factorization.

1243409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17106.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 1243409 is about 1115.0825081580. The cubic root of 1243409 is about 107.5320690334.

The spelling of 1243409 in words is "one million, two hundred forty-three thousand, four hundred nine".