113405561 has 2 divisors, whose sum is σ = 113405562. Its totient is φ = 113405560.

The previous prime is 113405503. The next prime is 113405563. The reversal of 113405561 is 165504311.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 83375161 + 30030400 = 9131^2 + 5480^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-113405561 is a prime.

Together with 113405563, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 113405561.

It is not a weakly prime, because it can be changed into another prime (113405563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 56702780 + 56702781.

It is an arithmetic number, because the mean of its divisors is an integer number (56702781).

Almost surely, 2^113405561 is an apocalyptic number.

It is an amenable number.

113405561 is a deficient number, since it is larger than the sum of its proper divisors (1).

113405561 is an equidigital number, since it uses as much as digits as its factorization.

113405561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1800, while the sum is 26.

The square root of 113405561 is about 10649.2047120900. The cubic root of 113405561 is about 484.0365057386.

Adding to 113405561 its reverse (165504311), we get a palindrome (278909872).

The spelling of 113405561 in words is "one hundred thirteen million, four hundred five thousand, five hundred sixty-one".