20158161 has 16 divisors (see below), whose sum is σ = 27941760. Its totient is φ = 12911360.

The previous prime is 20158109. The next prime is 20158163. The reversal of 20158161 is 16185102.

It is a cyclic number.

It is not a de Polignac number, because 20158161 - 2²¹ = 18061009 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20158163) 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 15 ways as a sum of consecutive naturals, for example, 22441 + ... + 23321.

It is an arithmetic number, because the mean of its divisors is an integer number (1746360).

Almost surely, 2^20158161 is an apocalyptic number.

It is an amenable number.

20158161 is a deficient number, since it is larger than the sum of its proper divisors (7783599).

20158161 is a wasteful number, since it uses less digits than its factorization.

20158161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1176.

The product of its (nonzero) digits is 480, while the sum is 24.

The square root of 20158161 is about 4489.7840705317. The cubic root of 20158161 is about 272.1554087744.

The spelling of 20158161 in words is "twenty million, one hundred fifty-eight thousand, one hundred sixty-one".