66404326743225 has 27 divisors (see below), whose sum is σ = 118937746389423. Its totient is φ = 35415575738640.

The previous prime is 66404326743203. The next prime is 66404326743229. The reversal of 66404326743225 is 52234762340466.

The square root of 66404326743225 is 8148885.

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

66404326743225 is a `hidden beast` number, since 6 + 6 + 404 + 3 + 2 + 6 + 7 + 4 + 3 + 225 = 666.

It can be written as a sum of positive squares in only one way, i.e., 23905557627561 + 42498769115664 = 4889331^2 + 6519108^2 .

It is not a de Polignac number, because 66404326743225 - 2²⁹ = 66403789872313 is a prime.

It is a super-2 number, since 2×66404326743225² (a number of 28 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66404326743229) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 121961646 + ... + 122504904.

Almost surely, 2^{66404326743225} is an apocalyptic number.

66404326743225 is the 8148885-th square number.

66404326743225 is the 4074443-rd centered octagonal number.

It is an amenable number.

66404326743225 is a deficient number, since it is larger than the sum of its proper divisors (52533419646198).

66404326743225 is an frugal number, since it uses more digits than its factorization.

66404326743225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1086534 (or 543267 counting only the distinct ones).

The product of its (nonzero) digits is 34836480, while the sum is 54.

The spelling of 66404326743225 in words is "sixty-six trillion, four hundred four billion, three hundred twenty-six million, seven hundred forty-three thousand, two hundred twenty-five".