1321440 has 48 divisors (see below), whose sum is σ = 4164048. Its totient is φ = 352256.

The previous prime is 1321429. The next prime is 1321447. The reversal of 1321440 is 441231.

1321440 = 111² + 112² + ... + 174².

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321447) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 897 + ... + 1856.

It is an arithmetic number, because the mean of its divisors is an integer number (86751).

2^1321440 is an apocalyptic number.

1321440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1321440 is an abundant number, since it is smaller than the sum of its proper divisors (2842608).

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

1321440 is a wasteful number, since it uses less digits than its factorization.

1321440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2771 (or 2763 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 1321440 is about 1149.5390380496. The cubic root of 1321440 is about 109.7360060544.

Adding to 1321440 its reverse (441231), we get a palindrome (1762671).

The spelling of 1321440 in words is "one million, three hundred twenty-one thousand, four hundred forty".