7243821 has 24 divisors (see below), whose sum is σ = 11398296. Its totient is φ = 4406400.

The previous prime is 7243787. The next prime is 7243837. The reversal of 7243821 is 1283427.

7243821 = 7⁴ + 8⁴ + ... + 32⁴.

7243821 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 114921 + 7128900 = 339^2 + 2670^2 .

It is a de Polignac number, because none of the positive numbers 2^k-7243821 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7243861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11511 + ... + 12123.

It is an arithmetic number, because the mean of its divisors is an integer number (474929).

Almost surely, 2^7243821 is an apocalyptic number.

It is an amenable number.

7243821 is a deficient number, since it is larger than the sum of its proper divisors (4154475).

7243821 is a wasteful number, since it uses less digits than its factorization.

7243821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 733 (or 730 counting only the distinct ones).

The product of its digits is 2688, while the sum is 27.

The square root of 7243821 is about 2691.4347474906. The cubic root of 7243821 is about 193.4888321580.

The spelling of 7243821 in words is "seven million, two hundred forty-three thousand, eight hundred twenty-one".