2001438720 has 480 divisors, whose sum is σ = 7610803200. Its totient is φ = 501645312.

The previous prime is 2001438661. The next prime is 2001438727. The reversal of 2001438720 is 278341002.

2001438720 is a `hidden beast` number, since 200 + 1 + 438 + 7 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (480).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (2001438727) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 15759297 + ... + 15759423.

It is an arithmetic number, because the mean of its divisors is an integer number (15855840).

Almost surely, 2^2001438720 is an apocalyptic number.

2001438720 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 2001438720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3805401600).

2001438720 is an abundant number, since it is smaller than the sum of its proper divisors (5609364480).

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

2001438720 is a wasteful number, since it uses less digits than its factorization.

2001438720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185 (or 156 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 2001438720 is about 44737.4420368443. The cubic root of 2001438720 is about 1260.2230897501.

Adding to 2001438720 its reverse (278341002), we get a palindrome (2279779722).

The spelling of 2001438720 in words is "two billion, one million, four hundred thirty-eight thousand, seven hundred twenty".