20111001201220 has 96 divisors (see below), whose sum is σ = 46435581200736. Its totient is φ = 7285351219200.

The previous prime is 20111001201217. The next prime is 20111001201289. The reversal of 20111001201220 is 2210210011102.

It can be written as a sum of positive squares in 16 ways, for example, as 4306114713924 + 15804886487296 = 2075118^2 + 3975536^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20111001201220.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8863771 + ... + 10899010.

It is an arithmetic number, because the mean of its divisors is an integer number (483703970841).

Almost surely, 2^{20111001201220} is an apocalyptic number.

20111001201220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20111001201220 is an abundant number, since it is smaller than the sum of its proper divisors (26324579999516).

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

20111001201220 is a wasteful number, since it uses less digits than its factorization.

20111001201220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19762921 (or 19762919 counting only the distinct ones).

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

Adding to 20111001201220 its reverse (2210210011102), we get a palindrome (22321211212322).

The spelling of 20111001201220 in words is "twenty trillion, one hundred eleven billion, one million, two hundred one thousand, two hundred twenty".