172208693454561 has 9 divisors (see below), whose sum is σ = 248745947411091. Its totient is φ = 114805769390712.

The previous prime is 172208693454559. The next prime is 172208693454569. The reversal of 172208693454561 is 165454396802271.

It is a happy number.

The square root of 172208693454561 is 13122831.

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

172208693454561 is a `hidden beast` number, since 1 + 7 + 2 + 2 + 0 + 8 + 69 + 3 + 4 + 5 + 4 + 561 = 666.

It can be written as a sum of positive squares in only one way, i.e., 43834264355025 + 128374429099536 = 6620745^2 + 11330244^2 .

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 172208693454561 - 2¹ = 172208693454559 is a prime.

It is not an unprimeable number, because it can be changed into a prime (172208693454569) 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, 37181355 + ... + 41555631.

It is a 1-persistent number, because it is pandigital, but 2⋅172208693454561 = 344417386909122 is not.

Almost surely, 2^{172208693454561} is an apocalyptic number.

172208693454561 is the 13122831-st square number.

172208693454561 is the 6561416-th centered octagonal number.

It is an amenable number.

172208693454561 is a deficient number, since it is larger than the sum of its proper divisors (76537253956530).

172208693454561 is an frugal number, since it uses more digits than its factorization.

172208693454561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8748560 (or 4374280 counting only the distinct ones).

The product of its (nonzero) digits is 87091200, while the sum is 63.

The spelling of 172208693454561 in words is "one hundred seventy-two trillion, two hundred eight billion, six hundred ninety-three million, four hundred fifty-four thousand, five hundred sixty-one".