16221911 has 2 divisors, whose sum is σ = 16221912. Its totient is φ = 16221910.

The previous prime is 16221901. The next prime is 16221917. The reversal of 16221911 is 11912261.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 16221911 - 2¹⁸ = 15959767 is a prime.

It is equal to p_1044464 and since 16221911 and 1044464 have the same sum of digits, it is a Honaker prime.

It is a plaindrome in base 14.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16221917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8110955 + 8110956.

It is an arithmetic number, because the mean of its divisors is an integer number (8110956).

Almost surely, 2^16221911 is an apocalyptic number.

16221911 is a deficient number, since it is larger than the sum of its proper divisors (1).

16221911 is an equidigital number, since it uses as much as digits as its factorization.

16221911 is an evil number, because the sum of its binary digits is even.

The product of its digits is 216, while the sum is 23.

The square root of 16221911 is about 4027.6433556113. The cubic root of 16221911 is about 253.1438250695.

The spelling of 16221911 in words is "sixteen million, two hundred twenty-one thousand, nine hundred eleven".