20135863 has 4 divisors (see below), whose sum is σ = 21966408. Its totient is φ = 18305320.

The previous prime is 20135827. The next prime is 20135867. The reversal of 20135863 is 36853102.

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

It is not a de Polignac number, because 20135863 - 2⁹ = 20135351 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 (20135867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 915256 + ... + 915277.

It is an arithmetic number, because the mean of its divisors is an integer number (5491602).

Almost surely, 2^20135863 is an apocalyptic number.

20135863 is a deficient number, since it is larger than the sum of its proper divisors (1830545).

20135863 is a wasteful number, since it uses less digits than its factorization.

20135863 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1830544.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 20135863 is about 4487.3001905377. The cubic root of 20135863 is about 272.0550232904.

Adding to 20135863 its reverse (36853102), we get a palindrome (56988965).

The spelling of 20135863 in words is "twenty million, one hundred thirty-five thousand, eight hundred sixty-three".