66683249361 has 9 divisors (see below), whose sum is σ = 96321368091. Its totient is φ = 44454983112.

The previous prime is 66683249351. The next prime is 66683249383. The reversal of 66683249361 is 16394238666.

The square root of 66683249361 is 258231.

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., 22648745025 + 44034504336 = 150495^2 + 209844^2 .

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 66683249361 - 2¹⁷ = 66683118289 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66683249298 and 66683249307.

It is not an unprimeable number, because it can be changed into a prime (66683249351) 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, 731655 + ... + 817731.

Almost surely, 2^66683249361 is an apocalyptic number.

66683249361 is the 258231-st square number.

66683249361 is the 129116-th centered octagonal number.

It is an amenable number.

66683249361 is a deficient number, since it is larger than the sum of its proper divisors (29638118730).

66683249361 is an frugal number, since it uses more digits than its factorization.

66683249361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 172160 (or 86080 counting only the distinct ones).

The product of its digits is 6718464, while the sum is 54.

It can be divided in two parts, 6668324 and 9361, that added together give a triangular number (6677685 = T₃₆₅₄).

The spelling of 66683249361 in words is "sixty-six billion, six hundred eighty-three million, two hundred forty-nine thousand, three hundred sixty-one".