16004381 has 2 divisors, whose sum is σ = 16004382. Its totient is φ = 16004380.

The previous prime is 16004369. The next prime is 16004383. The reversal of 16004381 is 18340061.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11764900 + 4239481 = 3430^2 + 2059^2 .

It is an emirp because it is prime and its reverse (18340061) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16004381 is a prime.

It is a super-2 number, since 2×16004381² = 512280422386322, which contains 22 as substring.

Together with 16004383, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16004383) 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 as a sum of consecutive naturals, namely, 8002190 + 8002191.

It is an arithmetic number, because the mean of its divisors is an integer number (8002191).

Almost surely, 2^16004381 is an apocalyptic number.

It is an amenable number.

16004381 is a deficient number, since it is larger than the sum of its proper divisors (1).

16004381 is an equidigital number, since it uses as much as digits as its factorization.

16004381 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 16004381 is about 4000.5475875185. The cubic root of 16004381 is about 252.0072066890.

The spelling of 16004381 in words is "sixteen million, four thousand, three hundred eighty-one".