4243509 has 14 divisors (see below), whose sum is σ = 6363446. Its totient is φ = 2828520.

The previous prime is 4243487. The next prime is 4243511. The reversal of 4243509 is 9053424.

It can be written as a sum of positive squares in only one way, i.e., 4100625 + 142884 = 2025^2 + 378^2 .

It is not a de Polignac number, because 4243509 - 2²¹ = 2146357 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4243529) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 2182 + ... + 3639.

Almost surely, 2^4243509 is an apocalyptic number.

It is an amenable number.

4243509 is a deficient number, since it is larger than the sum of its proper divisors (2119937).

4243509 is an frugal number, since it uses more digits than its factorization.

4243509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5839 (or 5824 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 4243509 is about 2059.9779125029. The cubic root of 4243509 is about 161.8980840452.

The spelling of 4243509 in words is "four million, two hundred forty-three thousand, five hundred nine".