3218021 has 4 divisors (see below), whose sum is σ = 3221952. Its totient is φ = 3214092.

The previous prime is 3218009. The next prime is 3218027. The reversal of 3218021 is 1208123.

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 a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1208123 = 7 ⋅172589.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3218021 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3218027) 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, 221 + ... + 2546.

It is an arithmetic number, because the mean of its divisors is an integer number (805488).

Almost surely, 2^3218021 is an apocalyptic number.

It is an amenable number.

3218021 is a deficient number, since it is larger than the sum of its proper divisors (3931).

3218021 is a wasteful number, since it uses less digits than its factorization.

3218021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3930.

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 3218021 is about 1793.8843329490. The cubic root of 3218021 is about 147.6373670029.

The spelling of 3218021 in words is "three million, two hundred eighteen thousand, twenty-one".