2016561 has 8 divisors (see below), whose sum is σ = 2734560. Its totient is φ = 1321472.

The previous prime is 2016559. The next prime is 2016577. The reversal of 2016561 is 1656102.

It is a happy number.

2016561 is nontrivially palindromic in base 9.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2016561 - 2¹ = 2016559 is a prime.

It is a zygodrome in base 6.

It is not an unprimeable number, because it can be changed into a prime (2016541) 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 in 7 ways as a sum of consecutive naturals, for example, 5520 + ... + 5873.

It is an arithmetic number, because the mean of its divisors is an integer number (341820).

2^2016561 is an apocalyptic number.

It is an amenable number.

2016561 is a deficient number, since it is larger than the sum of its proper divisors (717999).

2016561 is a wasteful number, since it uses less digits than its factorization.

2016561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11455.

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 2016561 is about 1420.0566890093. The cubic root of 2016561 is about 126.3389087160.

The spelling of 2016561 in words is "two million, sixteen thousand, five hundred sixty-one".