16534561 has 2 divisors, whose sum is σ = 16534562. Its totient is φ = 16534560.

The previous prime is 16534559. The next prime is 16534577. The reversal of 16534561 is 16543561.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16353936 + 180625 = 4044^2 + 425^2 .

It is a cyclic number.

It is not a de Polignac number, because 16534561 - 2¹ = 16534559 is a prime.

Together with 16534559, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (16534061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8267280 + 8267281.

It is an arithmetic number, because the mean of its divisors is an integer number (8267281).

Almost surely, 2^16534561 is an apocalyptic number.

It is an amenable number.

16534561 is a deficient number, since it is larger than the sum of its proper divisors (1).

16534561 is an equidigital number, since it uses as much as digits as its factorization.

16534561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10800, while the sum is 31.

The square root of 16534561 is about 4066.2711419678. The cubic root of 16534561 is about 254.7597943063.

The spelling of 16534561 in words is "sixteen million, five hundred thirty-four thousand, five hundred sixty-one".