66042553 has 2 divisors, whose sum is σ = 66042554. Its totient is φ = 66042552.

The previous prime is 66042551. The next prime is 66042563. The reversal of 66042553 is 35524066.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 34199104 + 31843449 = 5848^2 + 5643^2 .

It is a cyclic number.

It is not a de Polignac number, because 66042553 - 2¹ = 66042551 is a prime.

Together with 66042551, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (66042551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33021276 + 33021277.

It is an arithmetic number, because the mean of its divisors is an integer number (33021277).

Almost surely, 2^66042553 is an apocalyptic number.

It is an amenable number.

66042553 is a deficient number, since it is larger than the sum of its proper divisors (1).

66042553 is an equidigital number, since it uses as much as digits as its factorization.

66042553 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21600, while the sum is 31.

The square root of 66042553 is about 8126.6569387418. The cubic root of 66042553 is about 404.2108353661.

The spelling of 66042553 in words is "sixty-six million, forty-two thousand, five hundred fifty-three".