166146727321 has 9 divisors (see below), whose sum is σ = 168549139999. Its totient is φ = 163778099800.

The previous prime is 166146727303. The next prime is 166146727333. The reversal of 166146727321 is 123727641661.

The square root of 166146727321 is 407611.

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., 83052899721 + 83093827600 = 288189^2 + 288260^2 .

It is not a de Polignac number, because 166146727321 - 2²⁹ = 165609856409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166146725321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 28937511 + ... + 28943251.

Almost surely, 2^166146727321 is an apocalyptic number.

166146727321 is the 407611-st square number.

166146727321 is the 203806-th centered octagonal number.

It is an amenable number.

166146727321 is a deficient number, since it is larger than the sum of its proper divisors (2402412678).

166146727321 is an frugal number, since it uses more digits than its factorization.

166146727321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11624 (or 5812 counting only the distinct ones).

The product of its digits is 508032, while the sum is 46.

The spelling of 166146727321 in words is "one hundred sixty-six billion, one hundred forty-six million, seven hundred twenty-seven thousand, three hundred twenty-one".