20409803 has 4 divisors (see below), whose sum is σ = 20418888. Its totient is φ = 20400720.

The previous prime is 20409793. The next prime is 20409827. The reversal of 20409803 is 30890402.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 20409803 - 2⁸ = 20409547 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20409833) 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, 1568 + ... + 6578.

It is an arithmetic number, because the mean of its divisors is an integer number (5104722).

Almost surely, 2^20409803 is an apocalyptic number.

20409803 is a deficient number, since it is larger than the sum of its proper divisors (9085).

20409803 is an equidigital number, since it uses as much as digits as its factorization.

20409803 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9084.

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 20409803 is about 4517.7209962546. The cubic root of 20409803 is about 273.2832020230.

It can be divided in two parts, 20409 and 803, that added together give a palindrome (21212).

The spelling of 20409803 in words is "twenty million, four hundred nine thousand, eight hundred three".