4561 has 2 divisors, whose sum is σ = 4562.
Its totient is φ = 4560.
The previous prime is 4549. The next prime is 4567. The reversal of 4561 is 1654.
It can be divided in two parts, 4 and 561, that added together give a palindrome (565).
4561 is nontrivially palindromic in base 4.
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 3600 + 961 = 60^2 + 31^2
It is a cyclic number.
It is not a de Polignac number, because 4561 - 29 = 4049 is a prime.
It is an alternating number because its digits alternate between even and odd.
It is a pancake number, because a pancake can be divided into 4561 parts by 95 straight cuts.
4561 is a lucky number.
It is a plaindrome in base 11.
It is not a weakly prime, because it can be changed into another prime (4567) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2280 + 2281.
It is an arithmetic number, because the mean of its divisors is an integer number (2281).
It is an amenable number.
4561 is a deficient number, since it is larger than the sum of its proper divisors (1).
4561 is an equidigital number, since it uses as much as digits as its factorization.
4561 is an evil number, because the sum of its binary digits is even.
The product of its digits is 120, while the sum is 16.
The square root of 4561 is about 67.5351760196.
The cubic root of 4561 is about 16.5839007799.
The spelling of 4561 in words is "four thousand, five hundred sixty-one".