4138821 has 12 divisors (see below), whose sum is σ = 5996172. Its totient is φ = 2750976.

The previous prime is 4138819. The next prime is 4138829. The reversal of 4138821 is 1288314.

It can be written as a sum of positive squares in 2 ways, for example, as 3381921 + 756900 = 1839^2 + 870^2 .

It is not a de Polignac number, because 4138821 - 2¹ = 4138819 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4138829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4795 + ... + 5591.

It is an arithmetic number, because the mean of its divisors is an integer number (499681).

Almost surely, 2^4138821 is an apocalyptic number.

It is an amenable number.

4138821 is a deficient number, since it is larger than the sum of its proper divisors (1857351).

4138821 is a wasteful number, since it uses less digits than its factorization.

4138821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1380 (or 1377 counting only the distinct ones).

The product of its digits is 1536, while the sum is 27.

The square root of 4138821 is about 2034.4092508637. The cubic root of 4138821 is about 160.5556333182. Note that the first 3 decimals are identical.

The spelling of 4138821 in words is "four million, one hundred thirty-eight thousand, eight hundred twenty-one".