66215513333 has 4 divisors (see below), whose sum is σ = 66290673708. Its totient is φ = 66140352960.

The previous prime is 66215513297. The next prime is 66215513347. The reversal of 66215513333 is 33331551266.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 23060852164 + 43154661169 = 151858^2 + 207737^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66215513333 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66215513933) 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 in 3 ways as a sum of consecutive naturals, for example, 37578866 + ... + 37580627.

It is an arithmetic number, because the mean of its divisors is an integer number (16572668427).

Almost surely, 2^66215513333 is an apocalyptic number.

It is an amenable number.

66215513333 is a deficient number, since it is larger than the sum of its proper divisors (75160375).

66215513333 is an equidigital number, since it uses as much as digits as its factorization.

66215513333 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75160374.

The product of its digits is 145800, while the sum is 38.

The spelling of 66215513333 in words is "sixty-six billion, two hundred fifteen million, five hundred thirteen thousand, three hundred thirty-three".