1662409 has 4 divisors (see below), whose sum is σ = 1899904. Its totient is φ = 1424916.

The previous prime is 1662403. The next prime is 1662439. The reversal of 1662409 is 9042661.

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, and also an emirpimes, since its reverse is a distinct semiprime: 9042661 = 149 ⋅60689.

It is a cyclic number.

It is not a de Polignac number, because 1662409 - 2⁵ = 1662377 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1662403) 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, 118737 + ... + 118750.

It is an arithmetic number, because the mean of its divisors is an integer number (474976).

2^1662409 is an apocalyptic number.

It is an amenable number.

1662409 is a deficient number, since it is larger than the sum of its proper divisors (237495).

1662409 is an equidigital number, since it uses as much as digits as its factorization.

1662409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 237494.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 1662409 is about 1289.3444070534. The cubic root of 1662409 is about 118.4620636159.

The spelling of 1662409 in words is "one million, six hundred sixty-two thousand, four hundred nine".