16953221 has 2 divisors, whose sum is σ = 16953222. Its totient is φ = 16953220.

The previous prime is 16953203. The next prime is 16953239. The reversal of 16953221 is 12235961.

It is a balanced prime because it is at equal distance from previous prime (16953203) and next prime (16953239).

It can be written as a sum of positive squares in only one way, i.e., 16900321 + 52900 = 4111^2 + 230^2 .

It is an emirp because it is prime and its reverse (12235961) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16953221 is a prime.

It is equal to p_1088471 and since 16953221 and 1088471 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16953241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8476610 + 8476611.

It is an arithmetic number, because the mean of its divisors is an integer number (8476611).

Almost surely, 2^16953221 is an apocalyptic number.

It is an amenable number.

16953221 is a deficient number, since it is larger than the sum of its proper divisors (1).

16953221 is an equidigital number, since it uses as much as digits as its factorization.

16953221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3240, while the sum is 29.

The square root of 16953221 is about 4117.4289307771. The cubic root of 16953221 is about 256.8920953847.

The spelling of 16953221 in words is "sixteen million, nine hundred fifty-three thousand, two hundred twenty-one".