201123311220 has 144 divisors (see below), whose sum is σ = 657206261712. Its totient is φ = 49491947520.

The previous prime is 201123311183. The next prime is 201123311293. The reversal of 201123311220 is 22113321102.

201123311220 is a `hidden beast` number, since 2 + 0 + 112 + 331 + 1 + 220 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 41912735076 + 159210576144 = 204726^2 + 399012^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 201123311193 and 201123311202.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 8789314 + ... + 8812166.

It is an arithmetic number, because the mean of its divisors is an integer number (4563932373).

Almost surely, 2^201123311220 is an apocalyptic number.

201123311220 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 201123311220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (328603130856).

201123311220 is an abundant number, since it is smaller than the sum of its proper divisors (456082950492).

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

201123311220 is a wasteful number, since it uses less digits than its factorization.

201123311220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26642 (or 26637 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 201123311220 its reverse (22113321102), we get a palindrome (223236632322).

The spelling of 201123311220 in words is "two hundred one billion, one hundred twenty-three million, three hundred eleven thousand, two hundred twenty".