66237772689 has 45 divisors (see below), whose sum is σ = 105392456715. Its totient is φ = 40087483920.

The previous prime is 66237772661. The next prime is 66237772739. The reversal of 66237772689 is 98627773266.

The square root of 66237772689 is 257367.

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., 8839196289 + 57398576400 = 94017^2 + 239580^2 .

It is not a de Polignac number, because 66237772689 - 2⁷ = 66237772561 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (66237772649) 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 44 ways as a sum of consecutive naturals, for example, 93423867 + ... + 93424575.

Almost surely, 2^66237772689 is an apocalyptic number.

66237772689 is the 257367-th square number.

66237772689 is the 128684-th centered octagonal number.

It is an amenable number.

66237772689 is a deficient number, since it is larger than the sum of its proper divisors (39154684026).

66237772689 is an frugal number, since it uses more digits than its factorization.

66237772689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1468 (or 723 counting only the distinct ones).

The product of its digits is 64012032, while the sum is 63.

The spelling of 66237772689 in words is "sixty-six billion, two hundred thirty-seven million, seven hundred seventy-two thousand, six hundred eighty-nine".