20504207 has 4 divisors (see below), whose sum is σ = 20524560. Its totient is φ = 20483856.

The previous prime is 20504203. The next prime is 20504221. The reversal of 20504207 is 70240502.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 70240502 = 2 ⋅35120251.

It is a cyclic number.

It is not a de Polignac number, because 20504207 - 2² = 20504203 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20504203) 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, 8582 + ... + 10707.

It is an arithmetic number, because the mean of its divisors is an integer number (5131140).

Almost surely, 2^20504207 is an apocalyptic number.

20504207 is a deficient number, since it is larger than the sum of its proper divisors (20353).

20504207 is a wasteful number, since it uses less digits than its factorization.

20504207 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20352.

The product of its (nonzero) digits is 560, while the sum is 20.

The square root of 20504207 is about 4528.1571306659. The cubic root of 20504207 is about 273.7039043060.

Adding to 20504207 its reverse (70240502), we get a palindrome (90744709).

The spelling of 20504207 in words is "twenty million, five hundred four thousand, two hundred seven".