6661632553 has 2 divisors, whose sum is σ = 6661632554. Its totient is φ = 6661632552.

The previous prime is 6661632547. The next prime is 6661632557. The reversal of 6661632553 is 3552361666.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6450017344 + 211615209 = 80312^2 + 14547^2 .

It is a cyclic number.

It is not a de Polignac number, because 6661632553 - 2⁵ = 6661632521 is a prime.

It is not a weakly prime, because it can be changed into another prime (6661632557) 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, 3330816276 + 3330816277.

It is an arithmetic number, because the mean of its divisors is an integer number (3330816277).

Almost surely, 2^6661632553 is an apocalyptic number.

It is an amenable number.

6661632553 is a deficient number, since it is larger than the sum of its proper divisors (1).

6661632553 is an equidigital number, since it uses as much as digits as its factorization.

6661632553 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 583200, while the sum is 43.

The square root of 6661632553 is about 81618.8247465007. The cubic root of 6661632553 is about 1881.5982102385.

The spelling of 6661632553 in words is "six billion, six hundred sixty-one million, six hundred thirty-two thousand, five hundred fifty-three".