20504245 has 4 divisors (see below), whose sum is σ = 24605100. Its totient is φ = 16403392.

The previous prime is 20504221. The next prime is 20504353. The reversal of 20504245 is 54240502.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 15186609 + 5317636 = 3897^2 + 2306^2 .

It is a cyclic number.

It is not a de Polignac number, because 20504245 - 2⁷ = 20504117 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2050420 + ... + 2050429.

It is an arithmetic number, because the mean of its divisors is an integer number (6151275).

Almost surely, 2^20504245 is an apocalyptic number.

It is an amenable number.

20504245 is a deficient number, since it is larger than the sum of its proper divisors (4100855).

20504245 is an equidigital number, since it uses as much as digits as its factorization.

20504245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4100854.

The product of its (nonzero) digits is 1600, while the sum is 22.

The square root of 20504245 is about 4528.1613266314. The cubic root of 20504245 is about 273.7040733891.

Adding to 20504245 its reverse (54240502), we get a palindrome (74744747).

The spelling of 20504245 in words is "twenty million, five hundred four thousand, two hundred forty-five".