16509216 has 48 divisors (see below), whose sum is σ = 45226944. Its totient is φ = 5263104.

The previous prime is 16509211. The next prime is 16509221. The reversal of 16509216 is 61290561.

It is an interprime number because it is at equal distance from previous prime (16509211) and next prime (16509221).

It is a tau number, because it is divible by the number of its divisors (48).

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (16509211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1531 + ... + 5946.

It is an arithmetic number, because the mean of its divisors is an integer number (942228).

Almost surely, 2^16509216 is an apocalyptic number.

16509216 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

16509216 is an abundant number, since it is smaller than the sum of its proper divisors (28717728).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

16509216 is a wasteful number, since it uses less digits than its factorization.

16509216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7513 (or 7505 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 30.

The square root of 16509216 is about 4063.1534551380. The cubic root of 16509216 is about 254.6295582320.

Adding to 16509216 its reverse (61290561), we get a palindrome (77799777).

The spelling of 16509216 in words is "sixteen million, five hundred nine thousand, two hundred sixteen".