16401 has 16 divisors (see below), whose sum is σ = 27648. Its totient is φ = 8400.

The previous prime is 16381. The next prime is 16411. The reversal of 16401 is 10461.

16401 is nontrivially palindromic in base 5.

It is not a de Polignac number, because 16401 - 2⁵ = 16369 is a prime.

It is a Curzon number.

It is a nialpdrome in base 3 and base 7.

It is not an unprimeable number, because it can be changed into a prime (16411) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 196 + ... + 266.

It is an arithmetic number, because the mean of its divisors is an integer number (1728).

2¹⁶⁴⁰¹ is an apocalyptic number.

16401 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

16401 is a deficient number, since it is larger than the sum of its proper divisors (11247).

16401 is a wasteful number, since it uses less digits than its factorization.

16401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92.

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 16401 is about 128.0663890332. The cubic root of 16401 is about 25.4071982409.

Adding to 16401 its reverse (10461), we get a palindrome (26862).

The spelling of 16401 in words is "sixteen thousand, four hundred one".