2066520681 has 15 divisors (see below), whose sum is σ = 3087636013. Its totient is φ = 1377407700.

The previous prime is 2066520679. The next prime is 2066520713. The reversal of 2066520681 is 1860256602.

The square root of 2066520681 is 45459.

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

It is not a de Polignac number, because 2066520681 - 2¹ = 2066520679 is a prime.

It is a super-2 number, since 2×2066520681² = 8541015450001407522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2066520601) 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 14 ways as a sum of consecutive naturals, for example, 406606 + ... + 411656.

Almost surely, 2^2066520681 is an apocalyptic number.

2066520681 is the 45459-th square number.

2066520681 is the 22730-th centered octagonal number.

It is an amenable number.

2066520681 is a deficient number, since it is larger than the sum of its proper divisors (1021115332).

2066520681 is an frugal number, since it uses more digits than its factorization.

2066520681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10114 (or 5054 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The cubic root of 2066520681 is about 1273.7374519250.

Multiplying 2066520681 by its sum of digits (36), we get a square (74394744516 = 272754²).

The spelling of 2066520681 in words is "two billion, sixty-six million, five hundred twenty thousand, six hundred eighty-one".