20908205 has 8 divisors (see below), whose sum is σ = 25118304. Its totient is φ = 16707600.

The previous prime is 20908183. The next prime is 20908211. The reversal of 20908205 is 50280902.

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

It is not a de Polignac number, because 20908205 - 2⁶ = 20908141 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 4070 + ... + 7640.

It is an arithmetic number, because the mean of its divisors is an integer number (3139788).

Almost surely, 2^20908205 is an apocalyptic number.

It is an amenable number.

20908205 is a deficient number, since it is larger than the sum of its proper divisors (4210099).

20908205 is a wasteful number, since it uses less digits than its factorization.

20908205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4747.

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 20908205 is about 4572.5490702670. The cubic root of 20908205 is about 275.4898377131.

The spelling of 20908205 in words is "twenty million, nine hundred eight thousand, two hundred five".