20408047 has 8 divisors (see below), whose sum is σ = 22377600. Its totient is φ = 18457560.

The previous prime is 20408039. The next prime is 20408051. The reversal of 20408047 is 74080402.

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

It is not a de Polignac number, because 20408047 - 2³ = 20408039 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20408077) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2473 + ... + 6850.

It is an arithmetic number, because the mean of its divisors is an integer number (2797200).

Almost surely, 2^20408047 is an apocalyptic number.

20408047 is a deficient number, since it is larger than the sum of its proper divisors (1969553).

20408047 is a wasteful number, since it uses less digits than its factorization.

20408047 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9533.

The product of its (nonzero) digits is 1792, while the sum is 25.

The square root of 20408047 is about 4517.5266462966. The cubic root of 20408047 is about 273.2753643013.

Adding to 20408047 its reverse (74080402), we get a palindrome (94488449).

The spelling of 20408047 in words is "twenty million, four hundred eight thousand, forty-seven".