1011221200 has 180 divisors, whose sum is σ = 2829779820. Its totient is φ = 345804800.

The previous prime is 1011221161. The next prime is 1011221207. The reversal of 1011221200 is 21221101.

It can be written as a sum of positive squares in 6 ways, for example, as 113379904 + 897841296 = 10648^2 + 29964^2 .

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1011221207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 822186 + ... + 823414.

It is an arithmetic number, because the mean of its divisors is an integer number (15720999).

Almost surely, 2^1011221200 is an apocalyptic number.

1011221200 is a gapful number since it is divisible by the number (10) 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 1011221200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1414889910).

1011221200 is an abundant number, since it is smaller than the sum of its proper divisors (1818558620).

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

1011221200 is a wasteful number, since it uses less digits than its factorization.

1011221200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1286 (or 1264 counting only the distinct ones).

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

The square root of 1011221200 is about 31799.7044011418. The cubic root of 1011221200 is about 1003.7264959781.

Adding to 1011221200 its reverse (21221101), we get a palindrome (1032442301).

Subtracting from 1011221200 its reverse (21221101), we obtain a palindrome (990000099).

The spelling of 1011221200 in words is "one billion, eleven million, two hundred twenty-one thousand, two hundred".