3221621 has 8 divisors (see below), whose sum is σ = 3652320. Its totient is φ = 2817072.

The previous prime is 3221599. The next prime is 3221629. The reversal of 3221621 is 1261223.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 3221621 - 2⁶ = 3221557 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 3221621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3221629) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6275 + ... + 6768.

It is an arithmetic number, because the mean of its divisors is an integer number (456540).

Almost surely, 2^3221621 is an apocalyptic number.

It is an amenable number.

3221621 is a deficient number, since it is larger than the sum of its proper divisors (430699).

3221621 is a wasteful number, since it uses less digits than its factorization.

3221621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13075.

The product of its digits is 144, while the sum is 17.

The square root of 3221621 is about 1794.8874616532. The cubic root of 3221621 is about 147.6924004587.

Adding to 3221621 its reverse (1261223), we get a palindrome (4482844).

The spelling of 3221621 in words is "three million, two hundred twenty-one thousand, six hundred twenty-one".