66182193081 has 27 divisors (see below), whose sum is σ = 99040095661. Its totient is φ = 42585625824.

The previous prime is 66182193079. The next prime is 66182193097. The reversal of 66182193081 is 18039128166.

The square root of 66182193081 is 257259.

It is a perfect power (a square), and thus also a powerful number.

66182193081 is a `hidden beast` number, since 6 + 618 + 21 + 9 + 3 + 0 + 8 + 1 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 6360860025 + 59821333056 = 79755^2 + 244584^2 .

It is not a de Polignac number, because 66182193081 - 2¹ = 66182193079 is a prime.

It is a super-2 number, since 2×66182193081² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66182193031) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 22380055 + ... + 22383011.

Almost surely, 2^66182193081 is an apocalyptic number.

66182193081 is the 257259-th square number.

66182193081 is the 128630-th centered octagonal number.

It is an amenable number.

66182193081 is a deficient number, since it is larger than the sum of its proper divisors (32857902580).

66182193081 is an frugal number, since it uses more digits than its factorization.

66182193081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5978 (or 2989 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 45.

The spelling of 66182193081 in words is "sixty-six billion, one hundred eighty-two million, one hundred ninety-three thousand, eighty-one".