1440400 has 60 divisors (see below), whose sum is σ = 3740212. Its totient is φ = 529920.

The previous prime is 1440391. The next prime is 1440403. The reversal of 1440400 is 40441.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 350464 + 1089936 = 592^2 + 1044^2 .

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1440403) 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 11 ways as a sum of consecutive naturals, for example, 5062 + ... + 5338.

2^1440400 is an apocalyptic number.

1440400 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 1440400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1870106).

1440400 is an abundant number, since it is smaller than the sum of its proper divisors (2299812).

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

1440400 is a wasteful number, since it uses less digits than its factorization.

1440400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 308 (or 297 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 13.

The square root of 1440400 is about 1200.1666550942. The cubic root of 1440400 is about 112.9347784536.

Adding to 1440400 its reverse (40441), we get a palindrome (1480841).

The spelling of 1440400 in words is "one million, four hundred forty thousand, four hundred".