2421809 has 8 divisors (see below), whose sum is σ = 2622312. Its totient is φ = 2223360.

The previous prime is 2421791. The next prime is 2421817. The reversal of 2421809 is 9081242.

It can be written as a sum of positive squares in 4 ways, for example, as 10000 + 2411809 = 100^2 + 1553^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2421809 - 2⁸ = 2421553 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2421109) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2747 + ... + 3519.

It is an arithmetic number, because the mean of its divisors is an integer number (327789).

2^2421809 is an apocalyptic number.

It is an amenable number.

2421809 is a deficient number, since it is larger than the sum of its proper divisors (200503).

2421809 is a wasteful number, since it uses less digits than its factorization.

2421809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1027.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 2421809 is about 1556.2162446138. The cubic root of 2421809 is about 134.2909139701.

The spelling of 2421809 in words is "two million, four hundred twenty-one thousand, eight hundred nine".