61135561 has 2 divisors, whose sum is σ = 61135562. Its totient is φ = 61135560.

The previous prime is 61135549. The next prime is 61135577. The reversal of 61135561 is 16553116.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 54479161 + 6656400 = 7381^2 + 2580^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61135561 is a prime.

It is not a weakly prime, because it can be changed into another prime (61135531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30567780 + 30567781.

It is an arithmetic number, because the mean of its divisors is an integer number (30567781).

Almost surely, 2^61135561 is an apocalyptic number.

It is an amenable number.

61135561 is a deficient number, since it is larger than the sum of its proper divisors (1).

61135561 is an equidigital number, since it uses as much as digits as its factorization.

61135561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2700, while the sum is 28.

The square root of 61135561 is about 7818.9232634679. The cubic root of 61135561 is about 393.9411066602.

Adding to 61135561 its reverse (16553116), we get a palindrome (77688677).

The spelling of 61135561 in words is "sixty-one million, one hundred thirty-five thousand, five hundred sixty-one".