166256705919249 has 135 divisors (see below), whose sum is σ = 275261256080811. Its totient is φ = 99929973274560.

The previous prime is 166256705919181. The next prime is 166256705919253. The reversal of 166256705919249 is 942919507652661.

The square root of 166256705919249 is 12894057.

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

166256705919249 is a `hidden beast` number, since 1 + 6 + 6 + 2 + 5 + 6 + 7 + 0 + 591 + 9 + 24 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 8753402718225 + 157503303201024 = 2958615^2 + 12550032^2 .

It is not a de Polignac number, because 166256705919249 - 2¹⁹ = 166256705394961 is a prime.

It is not an unprimeable number, because it can be changed into a prime (166256705919749) 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, 177435117909 + ... + 177435118845.

Almost surely, 2^{166256705919249} is an apocalyptic number.

166256705919249 is the 12894057-th square number.

166256705919249 is the 6447029-th centered octagonal number.

It is an amenable number.

166256705919249 is a deficient number, since it is larger than the sum of its proper divisors (109004550161562).

166256705919249 is an frugal number, since it uses more digits than its factorization.

166256705919249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2186 (or 1090 counting only the distinct ones).

The product of its (nonzero) digits is 440899200, while the sum is 72.

The spelling of 166256705919249 in words is "one hundred sixty-six trillion, two hundred fifty-six billion, seven hundred five million, nine hundred nineteen thousand, two hundred forty-nine".