166902381 has 12 divisors (see below), whose sum is σ = 242084700. Its totient is φ = 110805120.

The previous prime is 166902377. The next prime is 166902389. The reversal of 166902381 is 183209661.

It can be written as a sum of positive squares in 2 ways, for example, as 119705481 + 47196900 = 10941^2 + 6870^2 .

It is not a de Polignac number, because 166902381 - 2² = 166902377 is a prime.

It is a super-2 number, since 2×166902381² = 55712809566938322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166902389) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 36306 + ... + 40643.

It is an arithmetic number, because the mean of its divisors is an integer number (20173725).

Almost surely, 2^166902381 is an apocalyptic number.

It is an amenable number.

166902381 is a deficient number, since it is larger than the sum of its proper divisors (75182319).

166902381 is a wasteful number, since it uses less digits than its factorization.

166902381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77196 (or 77193 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 166902381 is about 12919.0704386964. The cubic root of 166902381 is about 550.5805231324.

The spelling of 166902381 in words is "one hundred sixty-six million, nine hundred two thousand, three hundred eighty-one".