16408121 has 4 divisors (see below), whose sum is σ = 16473744. Its totient is φ = 16342500.

The previous prime is 16408087. The next prime is 16408127. The reversal of 16408121 is 12180461.

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 a de Polignac number, because none of the positive numbers 2^k-16408121 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (16408127) 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, 32435 + ... + 32936.

It is an arithmetic number, because the mean of its divisors is an integer number (4118436).

Almost surely, 2^16408121 is an apocalyptic number.

It is an amenable number.

16408121 is a deficient number, since it is larger than the sum of its proper divisors (65623).

16408121 is an equidigital number, since it uses as much as digits as its factorization.

16408121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65622.

The product of its (nonzero) digits is 384, while the sum is 23.

The square root of 16408121 is about 4050.6938911747. The cubic root of 16408121 is about 254.1087481513.

Adding to 16408121 its reverse (12180461), we get a palindrome (28588582).

The spelling of 16408121 in words is "sixteen million, four hundred eight thousand, one hundred twenty-one".