16493221 has 2 divisors, whose sum is σ = 16493222. Its totient is φ = 16493220.

The previous prime is 16493207. The next prime is 16493227. The reversal of 16493221 is 12239461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15124321 + 1368900 = 3889^2 + 1170^2 .

It is a cyclic number.

It is not a de Polignac number, because 16493221 - 2⁹ = 16492709 is a prime.

It is equal to p_1060795 and since 16493221 and 1060795 have the same sum of digits, it is a Honaker prime.

It is a nialpdrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 16493221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16493227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8246610 + 8246611.

It is an arithmetic number, because the mean of its divisors is an integer number (8246611).

Almost surely, 2^16493221 is an apocalyptic number.

It is an amenable number.

16493221 is a deficient number, since it is larger than the sum of its proper divisors (1).

16493221 is an equidigital number, since it uses as much as digits as its factorization.

16493221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2592, while the sum is 28.

The square root of 16493221 is about 4061.1846793762. The cubic root of 16493221 is about 254.5472988078.

The spelling of 16493221 in words is "sixteen million, four hundred ninety-three thousand, two hundred twenty-one".