2011213440 has 192 divisors, whose sum is σ = 7133429160. Its totient is φ = 521773056.

The previous prime is 2011213427. The next prime is 2011213447. The reversal of 2011213440 is 443121102.

2011213440 is a `hidden beast` number, since 2 + 0 + 11 + 213 + 440 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 1931075136 + 80138304 = 43944^2 + 8952^2 .

It is a tau number, because it is divible by the number of its divisors (192).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2011213447) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 208402 + ... + 217838.

Almost surely, 2^2011213440 is an apocalyptic number.

2011213440 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 2011213440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3566714580).

2011213440 is an abundant number, since it is smaller than the sum of its proper divisors (5122215720).

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

2011213440 is a wasteful number, since it uses less digits than its factorization.

2011213440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9499 (or 9484 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 2011213440 is about 44846.5543826948. The cubic root of 2011213440 is about 1262.2713377333.

Adding to 2011213440 its reverse (443121102), we get a palindrome (2454334542).

The spelling of 2011213440 in words is "two billion, eleven million, two hundred thirteen thousand, four hundred forty".