66368579641 has 81 divisors (see below), whose sum is σ = 88827590061. Its totient is φ = 49413768768.

The previous prime is 66368579587. The next prime is 66368579647. The reversal of 66368579641 is 14697586366.

The square root of 66368579641 is 257621.

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

66368579641 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 35919725625 + 30448854016 = 189525^2 + 174496^2 .

It is not a de Polignac number, because 66368579641 - 2⁹ = 66368579129 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66368579641.

It is not an unprimeable number, because it can be changed into a prime (66368579647) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 445426635 + ... + 445426783.

Almost surely, 2^66368579641 is an apocalyptic number.

66368579641 is the 257621-st square number.

66368579641 is the 128811-st centered octagonal number.

It is an amenable number.

66368579641 is a deficient number, since it is larger than the sum of its proper divisors (22459010420).

66368579641 is a wasteful number, since it uses less digits than its factorization.

66368579641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 376 (or 188 counting only the distinct ones).

The product of its digits is 39191040, while the sum is 61.

The spelling of 66368579641 in words is "sixty-six billion, three hundred sixty-eight million, five hundred seventy-nine thousand, six hundred forty-one".