66156005533 has 4 divisors (see below), whose sum is σ = 66521508508. Its totient is φ = 65790502560.

The previous prime is 66156005521. The next prime is 66156005543. The reversal of 66156005533 is 33550065166.

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 360164484 + 65795841049 = 18978^2 + 256507^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66156005533 is a prime.

It is a super-2 number, since 2×66156005533² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66156005543) 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, 182751216 + ... + 182751577.

It is an arithmetic number, because the mean of its divisors is an integer number (16630377127).

Almost surely, 2^66156005533 is an apocalyptic number.

It is an amenable number.

66156005533 is a deficient number, since it is larger than the sum of its proper divisors (365502975).

66156005533 is a wasteful number, since it uses less digits than its factorization.

66156005533 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 365502974.

The product of its (nonzero) digits is 243000, while the sum is 40.

The spelling of 66156005533 in words is "sixty-six billion, one hundred fifty-six million, five thousand, five hundred thirty-three".