66555213 has 8 divisors (see below), whose sum is σ = 89328576. Its totient is φ = 44076000.

The previous prime is 66555199. The next prime is 66555241. The reversal of 66555213 is 31255566.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 66555213 - 2¹² = 66551117 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66556213) 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 7 ways as a sum of consecutive naturals, for example, 73008 + ... + 73913.

It is an arithmetic number, because the mean of its divisors is an integer number (11166072).

Almost surely, 2^66555213 is an apocalyptic number.

It is an amenable number.

66555213 is a deficient number, since it is larger than the sum of its proper divisors (22773363).

66555213 is a wasteful number, since it uses less digits than its factorization.

66555213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 147075.

The product of its digits is 27000, while the sum is 33.

The square root of 66555213 is about 8158.1378389924. The cubic root of 66555213 is about 405.2540457622.

The spelling of 66555213 in words is "sixty-six million, five hundred fifty-five thousand, two hundred thirteen".