3221645 has 16 divisors (see below), whose sum is σ = 4475520. Its totient is φ = 2180544.

The previous prime is 3221641. The next prime is 3221677. The reversal of 3221645 is 5461223.

It is a cyclic number.

It is not a de Polignac number, because 3221645 - 2² = 3221641 is a prime.

It is a super-3 number, since 3×3221645³ (a number of 21 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 3221645.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3221641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2351 + ... + 3459.

It is an arithmetic number, because the mean of its divisors is an integer number (279720).

Almost surely, 2^3221645 is an apocalyptic number.

3221645 is a gapful number since it is divisible by the number (35) formed by its first and last digit.

It is an amenable number.

3221645 is a deficient number, since it is larger than the sum of its proper divisors (1253875).

3221645 is a wasteful number, since it uses less digits than its factorization.

3221645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1204.

The product of its digits is 1440, while the sum is 23.

The square root of 3221645 is about 1794.8941472967. The cubic root of 3221645 is about 147.6927672108.

Adding to 3221645 its reverse (5461223), we get a palindrome (8682868).

The spelling of 3221645 in words is "three million, two hundred twenty-one thousand, six hundred forty-five".