16365421 has 2 divisors, whose sum is σ = 16365422. Its totient is φ = 16365420.

The previous prime is 16365389. The next prime is 16365439. The reversal of 16365421 is 12456361.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9548100 + 6817321 = 3090^2 + 2611^2 .

It is an emirp because it is prime and its reverse (12456361) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16365421 - 2⁵ = 16365389 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 16365421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16365491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8182710 + 8182711.

It is an arithmetic number, because the mean of its divisors is an integer number (8182711).

Almost surely, 2^16365421 is an apocalyptic number.

It is an amenable number.

16365421 is a deficient number, since it is larger than the sum of its proper divisors (1).

16365421 is an equidigital number, since it uses as much as digits as its factorization.

16365421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4320, while the sum is 28.

The square root of 16365421 is about 4045.4197557237. The cubic root of 16365421 is about 253.8881283442. Note that the first 3 decimals are identical.

The spelling of 16365421 in words is "sixteen million, three hundred sixty-five thousand, four hundred twenty-one".