20205803 has 4 divisors (see below), whose sum is σ = 20217960. Its totient is φ = 20193648.

The previous prime is 20205781. The next prime is 20205821. The reversal of 20205803 is 30850202.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 30850202 = 2 ⋅15425101.

It is a cyclic number.

It is not a de Polignac number, because 20205803 - 2⁶ = 20205739 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20205883) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3098 + ... + 7071.

It is an arithmetic number, because the mean of its divisors is an integer number (5054490).

Almost surely, 2^20205803 is an apocalyptic number.

20205803 is a deficient number, since it is larger than the sum of its proper divisors (12157).

20205803 is a wasteful number, since it uses less digits than its factorization.

20205803 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12156.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 20205803 is about 4495.0865397676. The cubic root of 20205803 is about 272.3696450284.

The spelling of 20205803 in words is "twenty million, two hundred five thousand, eight hundred three".