2251440 has 120 divisors (see below), whose sum is σ = 7834320. Its totient is φ = 579072.

The previous prime is 2251427. The next prime is 2251451. The reversal of 2251440 is 441522.

2251440 is a `hidden beast` number, since 225 + 1 + 440 = 666.

It is a tau number, because it is divible by the number of its divisors (120).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 38131 + ... + 38189.

It is an arithmetic number, because the mean of its divisors is an integer number (65286).

2^2251440 is an apocalyptic number.

2251440 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 2251440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3917160).

2251440 is an abundant number, since it is smaller than the sum of its proper divisors (5582880).

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

2251440 is a wasteful number, since it uses less digits than its factorization.

2251440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131 (or 122 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 2251440 is about 1500.4799232246. The cubic root of 2251440 is about 131.0650183238.

Adding to 2251440 its reverse (441522), we get a palindrome (2692962).

The spelling of 2251440 in words is "two million, two hundred fifty-one thousand, four hundred forty".