20471 has 4 divisors (see below), whose sum is σ = 22344. Its totient is φ = 18600.

The previous prime is 20443. The next prime is 20477. The reversal of 20471 is 17402.

It is a happy number.

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 20471 - 2⁶ = 20407 is a prime.

It is a super-3 number, since 3×20471³ = 25735844841333, which contains 333 as substring.

It is a Duffinian number.

It is a nialpdrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20477) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 920 + ... + 941.

It is an arithmetic number, because the mean of its divisors is an integer number (5586).

2²⁰⁴⁷¹ is an apocalyptic number.

20471 is a deficient number, since it is larger than the sum of its proper divisors (1873).

20471 is a wasteful number, since it uses less digits than its factorization.

20471 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1872.

The product of its (nonzero) digits is 56, while the sum is 14.

The square root of 20471 is about 143.0769023987. The cubic root of 20471 is about 27.3556068035.

Adding to 20471 its reverse (17402), we get a palindrome (37873).

It can be divided in two parts, 2047 and 1, that added together give a 11-th power (2048 = 2¹¹).

The spelling of 20471 in words is "twenty thousand, four hundred seventy-one", and thus it is an iban number.