4218409 has 12 divisors (see below), whose sum is σ = 4629900. Its totient is φ = 3841344.

The previous prime is 4218377. The next prime is 4218413. The reversal of 4218409 is 9048124.

It can be written as a sum of positive squares in 6 ways, for example, as 3600 + 4214809 = 60^2 + 2053^2 .

It is not a de Polignac number, because 4218409 - 2⁵ = 4218377 is a prime.

It is a Duffinian number.

4218409 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (4218439) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18307 + ... + 18535.

It is an arithmetic number, because the mean of its divisors is an integer number (385825).

Almost surely, 2^4218409 is an apocalyptic number.

It is an amenable number.

4218409 is a deficient number, since it is larger than the sum of its proper divisors (411491).

4218409 is a wasteful number, since it uses less digits than its factorization.

4218409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 364 (or 351 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 4218409 is about 2053.8765785704. The cubic root of 4218409 is about 161.5782480811.

The spelling of 4218409 in words is "four million, two hundred eighteen thousand, four hundred nine".