66553369 has 2 divisors, whose sum is σ = 66553370. Its totient is φ = 66553368.

The previous prime is 66553337. The next prime is 66553381. The reversal of 66553369 is 96335566.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 64593369 + 1960000 = 8037^2 + 1400^2 .

It is a cyclic number.

It is not a de Polignac number, because 66553369 - 2⁵ = 66553337 is a prime.

It is a super-2 number, since 2×66553369² = 8858701850500322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (66553769) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33276684 + 33276685.

It is an arithmetic number, because the mean of its divisors is an integer number (33276685).

Almost surely, 2^66553369 is an apocalyptic number.

It is an amenable number.

66553369 is a deficient number, since it is larger than the sum of its proper divisors (1).

66553369 is an equidigital number, since it uses as much as digits as its factorization.

66553369 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 437400, while the sum is 43.

The square root of 66553369 is about 8158.0248222226. The cubic root of 66553369 is about 405.2503030282.

The spelling of 66553369 in words is "sixty-six million, five hundred fifty-three thousand, three hundred sixty-nine".