3839821 has 4 divisors (see below), whose sum is σ = 3852252. Its totient is φ = 3827392.

The previous prime is 3839813. The next prime is 3839833. The reversal of 3839821 is 1289383.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1289383 = 31 ⋅41593.

It can be written as a sum of positive squares in 2 ways, for example, as 617796 + 3222025 = 786^2 + 1795^2 .

It is a cyclic number.

It is not a de Polignac number, because 3839821 - 2³ = 3839813 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 (3839851) 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 3 ways as a sum of consecutive naturals, for example, 5740 + ... + 6373.

It is an arithmetic number, because the mean of its divisors is an integer number (963063).

Almost surely, 2^3839821 is an apocalyptic number.

It is an amenable number.

3839821 is a deficient number, since it is larger than the sum of its proper divisors (12431).

3839821 is a wasteful number, since it uses less digits than its factorization.

3839821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12430.

The product of its digits is 10368, while the sum is 34.

The square root of 3839821 is about 1959.5461209168. The cubic root of 3839821 is about 156.5922724100.

The spelling of 3839821 in words is "three million, eight hundred thirty-nine thousand, eight hundred twenty-one".