20868198911 has 4 divisors (see below), whose sum is σ = 23849370192. Its totient is φ = 17887027632.

The previous prime is 20868198877. The next prime is 20868198913. The reversal of 20868198911 is 11989186802.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 11989186802 = 2 ⋅5994593401.

It is a cyclic number.

It is not a de Polignac number, because 20868198911 - 2¹⁰ = 20868197887 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 (20868198913) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1490585630 + ... + 1490585643.

It is an arithmetic number, because the mean of its divisors is an integer number (5962342548).

Almost surely, 2^20868198911 is an apocalyptic number.

20868198911 is a deficient number, since it is larger than the sum of its proper divisors (2981171281).

20868198911 is an equidigital number, since it uses as much as digits as its factorization.

20868198911 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2981171280.

The product of its (nonzero) digits is 497664, while the sum is 53.

The spelling of 20868198911 in words is "twenty billion, eight hundred sixty-eight million, one hundred ninety-eight thousand, nine hundred eleven".