61555859 has 2 divisors, whose sum is σ = 61555860. Its totient is φ = 61555858.

The previous prime is 61555849. The next prime is 61555867. The reversal of 61555859 is 95855516.

61555859 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61555859 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (61555829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30777929 + 30777930.

It is an arithmetic number, because the mean of its divisors is an integer number (30777930).

Almost surely, 2^61555859 is an apocalyptic number.

61555859 is a deficient number, since it is larger than the sum of its proper divisors (1).

61555859 is an equidigital number, since it uses as much as digits as its factorization.

61555859 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 270000, while the sum is 44.

The square root of 61555859 is about 7845.7542021147. The cubic root of 61555859 is about 394.8418081498.

The spelling of 61555859 in words is "sixty-one million, five hundred fifty-five thousand, eight hundred fifty-nine".