20001021211120 has 80 divisors (see below), whose sum is σ = 46995945379488. Its totient is φ = 7915542773760.

The previous prime is 20001021211051. The next prime is 20001021211121. The reversal of 20001021211120 is 2111212010002.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×20001021211120² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20001021211120.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20001021211121) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25461672 + ... + 26235448.

Almost surely, 2^{20001021211120} is an apocalyptic number.

20001021211120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20001021211120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23497972689744).

20001021211120 is an abundant number, since it is smaller than the sum of its proper divisors (26994924168368).

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

20001021211120 is a wasteful number, since it uses less digits than its factorization.

20001021211120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 777218 (or 777212 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 20001021211120 its reverse (2111212010002), we get a palindrome (22112233221122).

The spelling of 20001021211120 in words is "twenty trillion, one billion, twenty-one million, two hundred eleven thousand, one hundred twenty".