166264751908161 has 27 divisors (see below), whose sum is σ = 253466591741571. Its totient is φ = 105008852797344.

The previous prime is 166264751908147. The next prime is 166264751908219. The reversal of 166264751908161 is 161809157462661.

The square root of 166264751908161 is 12894369.

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

166264751908161 is a `hidden beast` number, since 1 + 6 + 6 + 26 + 475 + 1 + 9 + 0 + 81 + 61 = 666.

It can be written as a sum of positive squares in only one way, i.e., 32629857185025 + 133634894723136 = 5712255^2 + 11560056^2 .

It is not a de Polignac number, because 166264751908161 - 2³¹ = 166262604424513 is a prime.

It is not an unprimeable number, because it can be changed into a prime (166264751900161) 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, 734865925 + ... + 735092141.

Almost surely, 2^{166264751908161} is an apocalyptic number.

166264751908161 is the 12894369-th square number.

166264751908161 is the 6447185-th centered octagonal number.

It is an amenable number.

166264751908161 is a deficient number, since it is larger than the sum of its proper divisors (87201839833410).

166264751908161 is an frugal number, since it uses more digits than its factorization.

166264751908161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 452478 (or 226239 counting only the distinct ones).

The product of its (nonzero) digits is 26127360, while the sum is 63.

The spelling of 166264751908161 in words is "one hundred sixty-six trillion, two hundred sixty-four billion, seven hundred fifty-one million, nine hundred eight thousand, one hundred sixty-one".