16187321 has 2 divisors, whose sum is σ = 16187322. Its totient is φ = 16187320.

The previous prime is 16187309. The next prime is 16187329. The reversal of 16187321 is 12378161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15840400 + 346921 = 3980^2 + 589^2 .

It is an emirp because it is prime and its reverse (12378161) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16187321 is a prime.

It is a super-2 number, since 2×16187321² = 524058722314082, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (16187329) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8093660 + 8093661.

It is an arithmetic number, because the mean of its divisors is an integer number (8093661).

Almost surely, 2^16187321 is an apocalyptic number.

It is an amenable number.

16187321 is a deficient number, since it is larger than the sum of its proper divisors (1).

16187321 is an equidigital number, since it uses as much as digits as its factorization.

16187321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2016, while the sum is 29.

The square root of 16187321 is about 4023.3469897587. The cubic root of 16187321 is about 252.9637707396.

The spelling of 16187321 in words is "sixteen million, one hundred eighty-seven thousand, three hundred twenty-one".