65990683606225 has 135 divisors (see below), whose sum is σ = 97032074418971. Its totient is φ = 44517887954400.

The previous prime is 65990683606219. The next prime is 65990683606229. The reversal of 65990683606225 is 52260638609956.

The square root of 65990683606225 is 8123465.

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., 23756646098241 + 42234037507984 = 4874079^2 + 6498772^2 .

It is not a de Polignac number, because 65990683606225 - 2⁷ = 65990683606097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65990683606229) by changing a digit.

It is a polite number, since it can be written in 134 ways as a sum of consecutive naturals, for example, 141307673442 + ... + 141307673908.

Almost surely, 2^{65990683606225} is an apocalyptic number.

65990683606225 is the 8123465-th square number.

65990683606225 is the 4061733-rd centered octagonal number.

It is an amenable number.

65990683606225 is a deficient number, since it is larger than the sum of its proper divisors (31041390812746).

65990683606225 is an frugal number, since it uses more digits than its factorization.

65990683606225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1114 (or 550 counting only the distinct ones).

The product of its (nonzero) digits is 251942400, while the sum is 67.

The spelling of 65990683606225 in words is "sixty-five trillion, nine hundred ninety billion, six hundred eighty-three million, six hundred six thousand, two hundred twenty-five".