55306561 has 2 divisors, whose sum is σ = 55306562. Its totient is φ = 55306560.

The previous prime is 55306523. The next prime is 55306579. The reversal of 55306561 is 16560355.

55306561 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 can be written as a sum of positive squares in only one way, i.e., 51480625 + 3825936 = 7175^2 + 1956^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55306561 is a prime.

It is equal to p_3299404 and since 55306561 and 3299404 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (55306501) 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, 27653280 + 27653281.

It is an arithmetic number, because the mean of its divisors is an integer number (27653281).

Almost surely, 2^55306561 is an apocalyptic number.

It is an amenable number.

55306561 is a deficient number, since it is larger than the sum of its proper divisors (1).

55306561 is an equidigital number, since it uses as much as digits as its factorization.

55306561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13500, while the sum is 31.

The square root of 55306561 is about 7436.8381050013. The cubic root of 55306561 is about 381.0005051855. Note that the first 3 decimals are identical.

The spelling of 55306561 in words is "fifty-five million, three hundred six thousand, five hundred sixty-one".