8172914686561 has 9 divisors (see below), whose sum is σ = 8543777284371. Its totient is φ = 7817507675472.

The previous prime is 8172914686487. The next prime is 8172914686577. The reversal of 8172914686561 is 1656864192718.

The square root of 8172914686561 is 2858831.

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., 3881156104225 + 4291758582336 = 1970065^2 + 2071656^2 .

It is not a de Polignac number, because 8172914686561 - 2¹¹ = 8172914684513 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 8172914686493 and 8172914686502.

It is not an unprimeable number, because it can be changed into a prime (8172914686061) 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, 65690965 + ... + 65815261.

Almost surely, 2^{8172914686561} is an apocalyptic number.

8172914686561 is the 2858831-st square number.

8172914686561 is the 1429416-th centered octagonal number.

It is an amenable number.

8172914686561 is a deficient number, since it is larger than the sum of its proper divisors (370862597810).

8172914686561 is an frugal number, since it uses more digits than its factorization.

8172914686561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 248640 (or 124320 counting only the distinct ones).

The product of its digits is 34836480, while the sum is 64.

Multiplying 8172914686561 by its sum of digits (64), we get a square (523066539939904 = 22870648²).

The spelling of 8172914686561 in words is "eight trillion, one hundred seventy-two billion, nine hundred fourteen million, six hundred eighty-six thousand, five hundred sixty-one".