16642 has 8 divisors (see below), whose sum is σ = 25596. Its totient is φ = 8112.

The previous prime is 16633. The next prime is 16649. The reversal of 16642 is 24661.

It is a Cunningham number, because it is equal to 129²+1.

It can be written as a sum of positive squares in 2 ways, for example, as 16641 + 1 = 129^2 + 1^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a plaindrome in base 11.

It is a nialpdrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (16649) by changing a digit.

16642 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (3) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28 + ... + 184.

2¹⁶⁶⁴² is an apocalyptic number.

16642 is a deficient number, since it is larger than the sum of its proper divisors (8954).

16642 is a wasteful number, since it uses less digits than its factorization.

16642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212.

The product of its digits is 288, while the sum is 19.

The square root of 16642 is about 129.0038759108. The cubic root of 16642 is about 25.5310399917.

Adding to 16642 its sum of digits (19), we get a palindrome (16661).

The spelling of 16642 in words is "sixteen thousand, six hundred forty-two".