20908005 has 16 divisors (see below), whose sum is σ = 33546624. Its totient is φ = 11119680.

The previous prime is 20908001. The next prime is 20908021. The reversal of 20908005 is 50080902.

It is not a de Polignac number, because 20908005 - 2² = 20908001 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20908001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4200 + ... + 7710.

It is an arithmetic number, because the mean of its divisors is an integer number (2096664).

Almost surely, 2^20908005 is an apocalyptic number.

It is an amenable number.

20908005 is a deficient number, since it is larger than the sum of its proper divisors (12638619).

20908005 is a wasteful number, since it uses less digits than its factorization.

20908005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3916.

The product of its (nonzero) digits is 720, while the sum is 24.

The square root of 20908005 is about 4572.5272005752. The cubic root of 20908005 is about 275.4889592997.

Adding to 20908005 its reverse (50080902), we get a palindrome (70988907).

The spelling of 20908005 in words is "twenty million, nine hundred eight thousand, five".