20811016617 has 4 divisors (see below), whose sum is σ = 27748022160. Its totient is φ = 13874011076.

The previous prime is 20811016601. The next prime is 20811016619. The reversal of 20811016617 is 71661011802.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20811016617 - 2⁴ = 20811016601 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20811016619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3468502767 + ... + 3468502772.

It is an arithmetic number, because the mean of its divisors is an integer number (6937005540).

Almost surely, 2^20811016617 is an apocalyptic number.

It is an amenable number.

20811016617 is a deficient number, since it is larger than the sum of its proper divisors (6937005543).

20811016617 is an equidigital number, since it uses as much as digits as its factorization.

20811016617 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6937005542.

The product of its (nonzero) digits is 4032, while the sum is 33.

The spelling of 20811016617 in words is "twenty billion, eight hundred eleven million, sixteen thousand, six hundred seventeen".