20304287 has 8 divisors (see below), whose sum is σ = 21166080. Its totient is φ = 19455480.

The previous prime is 20304281. The next prime is 20304289. The reversal of 20304287 is 78240302.

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

It is a cyclic number.

It is not a de Polignac number, because 20304287 - 2⁶ = 20304223 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 (20304281) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14 + ... + 6372.

It is an arithmetic number, because the mean of its divisors is an integer number (2645760).

Almost surely, 2^20304287 is an apocalyptic number.

20304287 is a deficient number, since it is larger than the sum of its proper divisors (861793).

20304287 is a wasteful number, since it uses less digits than its factorization.

20304287 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6493.

The product of its (nonzero) digits is 2688, while the sum is 26.

The square root of 20304287 is about 4506.0278516671. The cubic root of 20304287 is about 272.8114420243.

Adding to 20304287 its reverse (78240302), we get a palindrome (98544589).

The spelling of 20304287 in words is "twenty million, three hundred four thousand, two hundred eighty-seven".