16221325 has 12 divisors (see below), whose sum is σ = 20989728. Its totient is φ = 12412400.

The previous prime is 16221323. The next prime is 16221379. The reversal of 16221325 is 52312261.

It is not a de Polignac number, because 16221325 - 2¹ = 16221323 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 16221296 and 16221305.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16221323) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13531 + ... + 14680.

It is an arithmetic number, because the mean of its divisors is an integer number (1749144).

Almost surely, 2^16221325 is an apocalyptic number.

It is an amenable number.

16221325 is a deficient number, since it is larger than the sum of its proper divisors (4768403).

16221325 is a wasteful number, since it uses less digits than its factorization.

16221325 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28244 (or 28239 counting only the distinct ones).

The product of its digits is 720, while the sum is 22.

The square root of 16221325 is about 4027.5706076989. The cubic root of 16221325 is about 253.1407768452.

Adding to 16221325 its reverse (52312261), we get a palindrome (68533586).

The spelling of 16221325 in words is "sixteen million, two hundred twenty-one thousand, three hundred twenty-five".