16216321 has 4 divisors (see below), whose sum is σ = 17690544. Its totient is φ = 14742100.

The previous prime is 16216303. The next prime is 16216331. The reversal of 16216321 is 12361261.

16216321 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 16216321 - 2¹¹ = 16214273 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 16216292 and 16216301.

It is not an unprimeable number, because it can be changed into a prime (16216331) 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, 737095 + ... + 737116.

It is an arithmetic number, because the mean of its divisors is an integer number (4422636).

Almost surely, 2^16216321 is an apocalyptic number.

16216321 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

16216321 is a deficient number, since it is larger than the sum of its proper divisors (1474223).

16216321 is a wasteful number, since it uses less digits than its factorization.

16216321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1474222.

The product of its digits is 432, while the sum is 22.

The square root of 16216321 is about 4026.9493416233. The cubic root of 16216321 is about 253.1147443084.

Adding to 16216321 its reverse (12361261), we get a palindrome (28577582).

The spelling of 16216321 in words is "sixteen million, two hundred sixteen thousand, three hundred twenty-one".