20001122111964 has 192 divisors, whose sum is σ = 55939362619392. Its totient is φ = 5438264832000.

The previous prime is 20001122111963. The next prime is 20001122112029. The reversal of 20001122111964 is 46911122110002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20001122111963) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1388863164 + ... + 1388877564.

It is an arithmetic number, because the mean of its divisors is an integer number (291350846976).

Almost surely, 2^{20001122111964} 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 20001122111964, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27969681309696).

20001122111964 is an abundant number, since it is smaller than the sum of its proper divisors (35938240507428).

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

20001122111964 is a wasteful number, since it uses less digits than its factorization.

20001122111964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18056 (or 18054 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 30.

Adding to 20001122111964 its reverse (46911122110002), we get a palindrome (66912244221966).

The spelling of 20001122111964 in words is "twenty trillion, one billion, one hundred twenty-two million, one hundred eleven thousand, nine hundred sixty-four".