16561327 has 2 divisors, whose sum is σ = 16561328. Its totient is φ = 16561326.

The previous prime is 16561313. The next prime is 16561339. The reversal of 16561327 is 72316561.

It is a strong prime.

It is an emirp because it is prime and its reverse (72316561) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16561327 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16561367) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8280663 + 8280664.

It is an arithmetic number, because the mean of its divisors is an integer number (8280664).

Almost surely, 2^16561327 is an apocalyptic number.

16561327 is a deficient number, since it is larger than the sum of its proper divisors (1).

16561327 is an equidigital number, since it uses as much as digits as its factorization.

16561327 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7560, while the sum is 31.

The square root of 16561327 is about 4069.5610328388. The cubic root of 16561327 is about 254.8971878240.

Adding to 16561327 its reverse (72316561), we get a palindrome (88877888).

The spelling of 16561327 in words is "sixteen million, five hundred sixty-one thousand, three hundred twenty-seven".