16221745 has 8 divisors (see below), whose sum is σ = 19502784. Its totient is φ = 12952944.

The previous prime is 16221743. The next prime is 16221749. The reversal of 16221745 is 54712261.

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 16221745 - 2¹ = 16221743 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16221743) 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 7 ways as a sum of consecutive naturals, for example, 172 + ... + 5698.

It is an arithmetic number, because the mean of its divisors is an integer number (2437848).

Almost surely, 2^16221745 is an apocalyptic number.

It is an amenable number.

16221745 is a deficient number, since it is larger than the sum of its proper divisors (3281039).

16221745 is an equidigital number, since it uses as much as digits as its factorization.

16221745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6119.

The product of its digits is 3360, while the sum is 28.

The square root of 16221745 is about 4027.6227479743. The cubic root of 16221745 is about 253.1429615868.

The spelling of 16221745 in words is "sixteen million, two hundred twenty-one thousand, seven hundred forty-five".