20009471 has 8 divisors (see below), whose sum is σ = 20935680. Its totient is φ = 19087992.

The previous prime is 20009453. The next prime is 20009497. The reversal of 20009471 is 17490002.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20009471 - 2¹⁰ = 20008447 is a prime.

It is a super-3 number, since 3×20009471³ (a number of 23 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20009411) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9710 + ... + 11588.

It is an arithmetic number, because the mean of its divisors is an integer number (2616960).

Almost surely, 2^20009471 is an apocalyptic number.

20009471 is a deficient number, since it is larger than the sum of its proper divisors (926209).

20009471 is a wasteful number, since it uses less digits than its factorization.

20009471 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2365.

The product of its (nonzero) digits is 504, while the sum is 23.

The square root of 20009471 is about 4473.1947196607. The cubic root of 20009471 is about 271.4846019799.

Adding to 20009471 its reverse (17490002), we get a palindrome (37499473).

The spelling of 20009471 in words is "twenty million, nine thousand, four hundred seventy-one".