20111201020 has 96 divisors (see below), whose sum is σ = 44433156096. Its totient is φ = 7636204800.

The previous prime is 20111201009. The next prime is 20111201027. The reversal of 20111201020 is 2010211102.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a junction number, because it is equal to n+sod(n) for n = 20111200988 and 20111201006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20111201027) 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 31 ways as a sum of consecutive naturals, for example, 24317847 + ... + 24318673.

It is an arithmetic number, because the mean of its divisors is an integer number (462845376).

Almost surely, 2^20111201020 is an apocalyptic number.

20111201020 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 20111201020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22216578048).

20111201020 is an abundant number, since it is smaller than the sum of its proper divisors (24321955076).

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

20111201020 is a wasteful number, since it uses less digits than its factorization.

20111201020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1571 (or 1569 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 20111201020 its reverse (2010211102), we get a palindrome (22121412122).

The spelling of 20111201020 in words is "twenty billion, one hundred eleven million, two hundred one thousand, twenty".