75555551 has 2 divisors, whose sum is σ = 75555552. Its totient is φ = 75555550.

The previous prime is 75555541. The next prime is 75555563. The reversal of 75555551 is 15555557.

It is a weak prime.

It is an emirp because it is prime and its reverse (15555557) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 75555551 - 2¹⁰ = 75554527 is a prime.

It is a Chen prime.

It is a nialpdrome in base 10.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (75555541) 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, 37777775 + 37777776.

It is an arithmetic number, because the mean of its divisors is an integer number (37777776).

Almost surely, 2^75555551 is an apocalyptic number.

75555551 is a deficient number, since it is larger than the sum of its proper divisors (1).

75555551 is an equidigital number, since it uses as much as digits as its factorization.

75555551 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 109375, while the sum is 38.

The square root of 75555551 is about 8692.2696115572. The cubic root of 75555551 is about 422.7550385291.

The spelling of 75555551 in words is "seventy-five million, five hundred fifty-five thousand, five hundred fifty-one".