20549171 has 4 divisors (see below), whose sum is σ = 21104592. Its totient is φ = 19993752.

The previous prime is 20549161. The next prime is 20549173. The reversal of 20549171 is 17194502.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20549171 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20549173) 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, 277655 + ... + 277728.

It is an arithmetic number, because the mean of its divisors is an integer number (5276148).

Almost surely, 2^20549171 is an apocalyptic number.

20549171 is a deficient number, since it is larger than the sum of its proper divisors (555421).

20549171 is an equidigital number, since it uses as much as digits as its factorization.

20549171 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 555420.

The product of its (nonzero) digits is 2520, while the sum is 29.

The square root of 20549171 is about 4533.1193454397. The cubic root of 20549171 is about 273.9038281128.

The spelling of 20549171 in words is "twenty million, five hundred forty-nine thousand, one hundred seventy-one".