66091872241 has 4 divisors (see below), whose sum is σ = 66092446372. Its totient is φ = 66091298112.

The previous prime is 66091872227. The next prime is 66091872251. The reversal of 66091872241 is 14227819066.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 14227819066 = 2 ⋅7113909533.

It can be written as a sum of positive squares in 2 ways, for example, as 27133007841 + 38958864400 = 164721^2 + 197380^2 .

It is a cyclic number.

It is not a de Polignac number, because 66091872241 - 2⁷ = 66091872113 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66091872191 and 66091872200.

It is not an unprimeable number, because it can be changed into a prime (66091872251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 48060 + ... + 366733.

It is an arithmetic number, because the mean of its divisors is an integer number (16523111593).

Almost surely, 2^66091872241 is an apocalyptic number.

It is an amenable number.

66091872241 is a deficient number, since it is larger than the sum of its proper divisors (574131).

66091872241 is a wasteful number, since it uses less digits than its factorization.

66091872241 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 574130.

The product of its (nonzero) digits is 290304, while the sum is 46.

The spelling of 66091872241 in words is "sixty-six billion, ninety-one million, eight hundred seventy-two thousand, two hundred forty-one".