66656396041 has 9 divisors (see below), whose sum is σ = 70812668199. Its totient is φ = 62731300704.

The previous prime is 66656396033. The next prime is 66656396057. The reversal of 66656396041 is 14069365666.

The square root of 66656396041 is 258179.

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

It can be written as a sum of positive squares in only one way, i.e., 51895118025 + 14761278016 = 227805^2 + 121496^2 .

It is not a de Polignac number, because 66656396041 - 2³ = 66656396033 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66656396041.

It is not an unprimeable number, because it can be changed into a prime (66656399041) 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 8 ways as a sum of consecutive naturals, for example, 4381450 + ... + 4396636.

Almost surely, 2^66656396041 is an apocalyptic number.

66656396041 is the 258179-th square number.

66656396041 is the 129090-th centered octagonal number.

It is an amenable number.

66656396041 is a deficient number, since it is larger than the sum of its proper divisors (4156272158).

66656396041 is an frugal number, since it uses more digits than its factorization.

66656396041 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30408 (or 15204 counting only the distinct ones).

The product of its (nonzero) digits is 4199040, while the sum is 52.

The spelling of 66656396041 in words is "sixty-six billion, six hundred fifty-six million, three hundred ninety-six thousand, forty-one".