3938021 has 4 divisors (see below), whose sum is σ = 4044492. Its totient is φ = 3831552.

The previous prime is 3937993. The next prime is 3938029. The reversal of 3938021 is 1208393.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1208393 = 41 ⋅29473.

It can be written as a sum of positive squares in 2 ways, for example, as 3189796 + 748225 = 1786^2 + 865^2 .

It is a cyclic number.

It is not a de Polignac number, because 3938021 - 2¹⁰ = 3936997 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 (3938029) 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, 53180 + ... + 53253.

It is an arithmetic number, because the mean of its divisors is an integer number (1011123).

Almost surely, 2^3938021 is an apocalyptic number.

It is an amenable number.

3938021 is a deficient number, since it is larger than the sum of its proper divisors (106471).

3938021 is a wasteful number, since it uses less digits than its factorization.

3938021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106470.

The product of its (nonzero) digits is 1296, while the sum is 26.

The square root of 3938021 is about 1984.4447586164. Note that the first 3 decimals coincide. The cubic root of 3938021 is about 157.9159543398.

The spelling of 3938021 in words is "three million, nine hundred thirty-eight thousand, twenty-one".