3828021 has 4 divisors (see below), whose sum is σ = 5104032. Its totient is φ = 2552012.

The previous prime is 3828007. The next prime is 3828023. The reversal of 3828021 is 1208283.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1208283 = 3 ⋅402761.

It is a cyclic number.

It is not a de Polignac number, because 3828021 - 2⁷ = 3827893 is a prime.

It is a D-number.

It is a Curzon number.

3828021 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 3827982 and 3828000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3828023) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 638001 + ... + 638006.

It is an arithmetic number, because the mean of its divisors is an integer number (1276008).

Almost surely, 2^3828021 is an apocalyptic number.

It is an amenable number.

3828021 is a deficient number, since it is larger than the sum of its proper divisors (1276011).

3828021 is a wasteful number, since it uses less digits than its factorization.

3828021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1276010.

The product of its (nonzero) digits is 768, while the sum is 24.

The square root of 3828021 is about 1956.5329028667. The cubic root of 3828021 is about 156.4317020048.

The spelling of 3828021 in words is "three million, eight hundred twenty-eight thousand, twenty-one".