66363553 has 2 divisors, whose sum is σ = 66363554. Its totient is φ = 66363552.

The previous prime is 66363551. The next prime is 66363589. The reversal of 66363553 is 35536366.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 61732449 + 4631104 = 7857^2 + 2152^2 .

It is a cyclic number.

It is not a de Polignac number, because 66363553 - 2¹ = 66363551 is a prime.

Together with 66363551, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (66363551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33181776 + 33181777.

It is an arithmetic number, because the mean of its divisors is an integer number (33181777).

Almost surely, 2^66363553 is an apocalyptic number.

It is an amenable number.

66363553 is a deficient number, since it is larger than the sum of its proper divisors (1).

66363553 is an equidigital number, since it uses as much as digits as its factorization.

66363553 is an evil number, because the sum of its binary digits is even.

The product of its digits is 145800, while the sum is 37.

The square root of 66363553 is about 8146.3828169317. The cubic root of 66363553 is about 404.8646664625.

The spelling of 66363553 in words is "sixty-six million, three hundred sixty-three thousand, five hundred fifty-three".