201040561 has 4 divisors (see below), whose sum is σ = 201078900. Its totient is φ = 201002224.

The previous prime is 201040531. The next prime is 201040621. The reversal of 201040561 is 165040102.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 117592336 + 83448225 = 10844^2 + 9135^2 .

It is a cyclic number.

It is not a de Polignac number, because 201040561 - 2¹⁹ = 200516273 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (201040531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9766 + ... + 22303.

It is an arithmetic number, because the mean of its divisors is an integer number (50269725).

Almost surely, 2^201040561 is an apocalyptic number.

It is an amenable number.

201040561 is a deficient number, since it is larger than the sum of its proper divisors (38339).

201040561 is an equidigital number, since it uses as much as digits as its factorization.

201040561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38338.

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 201040561 is about 14178.8772827752. The cubic root of 201040561 is about 585.8160000771.

Adding to 201040561 its reverse (165040102), we get a palindrome (366080663).

It can be divided in two parts, 201040 and 561, that added together give a square (201601 = 449²).

The spelling of 201040561 in words is "two hundred one million, forty thousand, five hundred sixty-one".