66120885675625 has 45 divisors (see below), whose sum is σ = 90821911296963. Its totient is φ = 48086290560000.

The previous prime is 66120885675623. The next prime is 66120885675653. The reversal of 66120885675625 is 52657658802166.

The square root of 66120885675625 is 8131475.

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

It can be written as a sum of positive squares in 7 ways, for example, as 48829726181929 + 17291159493696 = 6987827^2 + 4158264^2 .

It is not a de Polignac number, because 66120885675625 - 2¹ = 66120885675623 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66120885675623) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 2236140841 + ... + 2236170409.

Almost surely, 2^{66120885675625} is an apocalyptic number.

66120885675625 is the 8131475-th square number.

66120885675625 is the 4065738-th centered octagonal number.

It is an amenable number.

66120885675625 is a deficient number, since it is larger than the sum of its proper divisors (24701025621338).

66120885675625 is an frugal number, since it uses more digits than its factorization.

66120885675625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59180 (or 29585 counting only the distinct ones).

The product of its (nonzero) digits is 290304000, while the sum is 67.

The spelling of 66120885675625 in words is "sixty-six trillion, one hundred twenty billion, eight hundred eighty-five million, six hundred seventy-five thousand, six hundred twenty-five".