61040561 has 4 divisors (see below), whose sum is σ = 61726500. Its totient is φ = 60354624.

The previous prime is 61040543. The next prime is 61040587. The reversal of 61040561 is 16504016.

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 27040000 + 34000561 = 5200^2 + 5831^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61040561 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (61070561) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 342836 + ... + 343013.

It is an arithmetic number, because the mean of its divisors is an integer number (15431625).

Almost surely, 2^61040561 is an apocalyptic number.

It is an amenable number.

61040561 is a deficient number, since it is larger than the sum of its proper divisors (685939).

61040561 is an equidigital number, since it uses as much as digits as its factorization.

61040561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 685938.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 61040561 is about 7812.8458963428. The cubic root of 61040561 is about 393.7369493953.

Adding to 61040561 its reverse (16504016), we get a palindrome (77544577).

The spelling of 61040561 in words is "sixty-one million, forty thousand, five hundred sixty-one".