20471409 has 24 divisors (see below), whose sum is σ = 34437312. Its totient is φ = 11475360.

The previous prime is 20471389. The next prime is 20471411. The reversal of 20471409 is 90417402.

It is a happy number.

It is not a de Polignac number, because 20471409 - 2¹⁶ = 20405873 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20471459) 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 23 ways as a sum of consecutive naturals, for example, 274 + ... + 6404.

It is an arithmetic number, because the mean of its divisors is an integer number (1434888).

Almost surely, 2^20471409 is an apocalyptic number.

It is an amenable number.

20471409 is a deficient number, since it is larger than the sum of its proper divisors (13965903).

20471409 is a wasteful number, since it uses less digits than its factorization.

20471409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6197 (or 6194 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 20471409 is about 4524.5341196636. The cubic root of 20471409 is about 273.5578898590.

The spelling of 20471409 in words is "twenty million, four hundred seventy-one thousand, four hundred nine".