16019221 has 4 divisors (see below), whose sum is σ = 16054732. Its totient is φ = 15983712.

The previous prime is 16019209. The next prime is 16019239. The reversal of 16019221 is 12291061.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8346321 + 7672900 = 2889^2 + 2770^2 .

It is a cyclic number.

It is not a de Polignac number, because 16019221 - 2⁷ = 16019093 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 16019192 and 16019201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16079221) 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, 17070 + ... + 17983.

It is an arithmetic number, because the mean of its divisors is an integer number (4013683).

Almost surely, 2^16019221 is an apocalyptic number.

It is an amenable number.

16019221 is a deficient number, since it is larger than the sum of its proper divisors (35511).

16019221 is an equidigital number, since it uses as much as digits as its factorization.

16019221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35510.

The product of its (nonzero) digits is 216, while the sum is 22.

The square root of 16019221 is about 4002.4019038572. The cubic root of 16019221 is about 252.0850735273.

The spelling of 16019221 in words is "sixteen million, nineteen thousand, two hundred twenty-one".