20311111216 has 160 divisors (see below), whose sum is σ = 48967151616. Its totient is φ = 8042496000.

The previous prime is 20311111157. The next prime is 20311111217. The reversal of 20311111216 is 61211111302.

It is a junction number, because it is equal to n+sod(n) for n = 20311111193 and 20311111202.

It is not an unprimeable number, because it can be changed into a prime (20311111217) 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 31 ways as a sum of consecutive naturals, for example, 2128536 + ... + 2138056.

Almost surely, 2^20311111216 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20311111216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24483575808).

20311111216 is an abundant number, since it is smaller than the sum of its proper divisors (28656040400).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20311111216 is a wasteful number, since it uses less digits than its factorization.

20311111216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9611 (or 9605 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 19.

Adding to 20311111216 its reverse (61211111302), we get a palindrome (81522222518).

The spelling of 20311111216 in words is "twenty billion, three hundred eleven million, one hundred eleven thousand, two hundred sixteen".