66582061225 has 9 divisors (see below), whose sum is σ = 82563355767. Its totient is φ = 53264616840.

The previous prime is 66582061223. The next prime is 66582061277. The reversal of 66582061225 is 52216028566.

The square root of 66582061225 is 258035.

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., 23969542041 + 42612519184 = 154821^2 + 206428^2 .

It is not a de Polignac number, because 66582061225 - 2¹ = 66582061223 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66582061223) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1264372 + ... + 1315978.

Almost surely, 2^66582061225 is an apocalyptic number.

66582061225 is the 258035-th square number.

66582061225 is the 129018-th centered octagonal number.

It is an amenable number.

66582061225 is a deficient number, since it is larger than the sum of its proper divisors (15981294542).

66582061225 is an frugal number, since it uses more digits than its factorization.

66582061225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103224 (or 51612 counting only the distinct ones).

The product of its (nonzero) digits is 345600, while the sum is 43.

The spelling of 66582061225 in words is "sixty-six billion, five hundred eighty-two million, sixty-one thousand, two hundred twenty-five".