16442 has 4 divisors (see below), whose sum is σ = 24666. Its totient is φ = 8220.

The previous prime is 16433. The next prime is 16447. The reversal of 16442 is 24461.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24461 = 61 ⋅401.

It can be written as a sum of positive squares in only one way, i.e., 10201 + 6241 = 101^2 + 79^2 .

It is a super-3 number, since 3×16442³ = 13334759468664, which contains 333 as substring.

It is a plaindrome in base 9.

It is a nialpdrome in base 12.

It is a self number, because there is not a number n which added to its sum of digits gives 16442.

It is not an unprimeable number, because it can be changed into a prime (16447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4109 + ... + 4112.

2¹⁶⁴⁴² is an apocalyptic number.

16442 is a deficient number, since it is larger than the sum of its proper divisors (8224).

16442 is an equidigital number, since it uses as much as digits as its factorization.

16442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8223.

The product of its digits is 192, while the sum is 17.

The square root of 16442 is about 128.2263623441. The cubic root of 16442 is about 25.4283519979.

The spelling of 16442 in words is "sixteen thousand, four hundred forty-two".