20836288509991 has 4 divisors (see below), whose sum is σ = 20842315788112. Its totient is φ = 20830261231872.

The previous prime is 20836288509917. The next prime is 20836288510001. The reversal of 20836288509991 is 19990588263802.

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 20836288509991 - 2⁹ = 20836288509479 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20836288509991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20836288509391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3013633875 + ... + 3013640788.

It is an arithmetic number, because the mean of its divisors is an integer number (5210578947028).

Almost surely, 2^{20836288509991} is an apocalyptic number.

20836288509991 is a deficient number, since it is larger than the sum of its proper divisors (6027278121).

20836288509991 is an equidigital number, since it uses as much as digits as its factorization.

20836288509991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6027278120.

The product of its (nonzero) digits is 134369280, while the sum is 70.

The spelling of 20836288509991 in words is "twenty trillion, eight hundred thirty-six billion, two hundred eighty-eight million, five hundred nine thousand, nine hundred ninety-one".