75556561 has 2 divisors, whose sum is σ = 75556562. Its totient is φ = 75556560.

The previous prime is 75556549. The next prime is 75556573. The reversal of 75556561 is 16565557.

It is a balanced prime because it is at equal distance from previous prime (75556549) and next prime (75556573).

It can be written as a sum of positive squares in only one way, i.e., 74304400 + 1252161 = 8620^2 + 1119^2 .

It is a cyclic number.

It is not a de Polignac number, because 75556561 - 2⁵ = 75556529 is a prime.

It is not a weakly prime, because it can be changed into another prime (75556361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37778280 + 37778281.

It is an arithmetic number, because the mean of its divisors is an integer number (37778281).

Almost surely, 2^75556561 is an apocalyptic number.

It is an amenable number.

75556561 is a deficient number, since it is larger than the sum of its proper divisors (1).

75556561 is an equidigital number, since it uses as much as digits as its factorization.

75556561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 157500, while the sum is 40.

The square root of 75556561 is about 8692.3277089627. The cubic root of 75556561 is about 422.7569222676.

The spelling of 75556561 in words is "seventy-five million, five hundred fifty-six thousand, five hundred sixty-one".