20165171 has 4 divisors (see below), whose sum is σ = 21716352. Its totient is φ = 18613992.

The previous prime is 20165161. The next prime is 20165183. The reversal of 20165171 is 17156102.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20165171 - 2¹⁰ = 20164147 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20165141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 775571 + ... + 775596.

It is an arithmetic number, because the mean of its divisors is an integer number (5429088).

Almost surely, 2^20165171 is an apocalyptic number.

20165171 is a deficient number, since it is larger than the sum of its proper divisors (1551181).

20165171 is a wasteful number, since it uses less digits than its factorization.

20165171 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1551180.

The product of its (nonzero) digits is 420, while the sum is 23.

The square root of 20165171 is about 4490.5646638257. The cubic root of 20165171 is about 272.1869524639.

The spelling of 20165171 in words is "twenty million, one hundred sixty-five thousand, one hundred seventy-one".