201101220 has 72 divisors (see below), whose sum is σ = 611203320. Its totient is φ = 53521920.

The previous prime is 201101209. The next prime is 201101231. The reversal of 201101220 is 22101102.

It is an interprime number because it is at equal distance from previous prime (201101209) and next prime (201101231).

It can be written as a sum of positive squares in 4 ways, for example, as 48776256 + 152324964 = 6984^2 + 12342^2 .

It is a Harshad number since it is a multiple of its sum of digits (9).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 144930 + ... + 146310.

It is an arithmetic number, because the mean of its divisors is an integer number (8488935).

Almost surely, 2^201101220 is an apocalyptic number.

201101220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

201101220 is an abundant number, since it is smaller than the sum of its proper divisors (410102100).

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

201101220 is a wasteful number, since it uses less digits than its factorization.

201101220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2205 (or 2200 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 201101220 is about 14181.0161836167. The cubic root of 201101220 is about 585.8749126323.

Adding to 201101220 its reverse (22101102), we get a palindrome (223202322).

The spelling of 201101220 in words is "two hundred one million, one hundred one thousand, two hundred twenty".