20530087 has 4 divisors (see below), whose sum is σ = 20558176. Its totient is φ = 20502000.

The previous prime is 20530039. The next prime is 20530093. The reversal of 20530087 is 78003502.

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

It is a cyclic number.

It is not a de Polignac number, because 20530087 - 2⁷ = 20529959 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 (20530487) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12918 + ... + 14419.

It is an arithmetic number, because the mean of its divisors is an integer number (5139544).

Almost surely, 2^20530087 is an apocalyptic number.

20530087 is a deficient number, since it is larger than the sum of its proper divisors (28089).

20530087 is an equidigital number, since it uses as much as digits as its factorization.

20530087 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28088.

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 20530087 is about 4531.0139041941. The cubic root of 20530087 is about 273.8190104227.

Adding to 20530087 its reverse (78003502), we get a palindrome (98533589).

The spelling of 20530087 in words is "twenty million, five hundred thirty thousand, eighty-seven".