66555533 has 4 divisors (see below), whose sum is σ = 72606048. Its totient is φ = 60505020.

The previous prime is 66555521. The next prime is 66555539. The reversal of 66555533 is 33555566.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 66555533 - 2¹² = 66551437 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a nialpdrome in base 10.

It is a zygodrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66555539) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3025241 + ... + 3025262.

It is an arithmetic number, because the mean of its divisors is an integer number (18151512).

Almost surely, 2^66555533 is an apocalyptic number.

It is an amenable number.

66555533 is a deficient number, since it is larger than the sum of its proper divisors (6050515).

66555533 is a wasteful number, since it uses less digits than its factorization.

66555533 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6050514.

The product of its digits is 202500, while the sum is 38.

The square root of 66555533 is about 8158.1574512876. The cubic root of 66555533 is about 405.2546952534.

The spelling of 66555533 in words is "sixty-six million, five hundred fifty-five thousand, five hundred thirty-three".