1321280 has 28 divisors (see below), whose sum is σ = 3147060. Its totient is φ = 528384.

The previous prime is 1321273. The next prime is 1321283. The reversal of 1321280 is 821231.

It can be written as a sum of positive squares in 2 ways, for example, as 602176 + 719104 = 776^2 + 848^2 .

It is a zygodrome in base 4.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321283) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1745 + ... + 2384.

It is an arithmetic number, because the mean of its divisors is an integer number (112395).

2^1321280 is an apocalyptic number.

1321280 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1321280 is an abundant number, since it is smaller than the sum of its proper divisors (1825780).

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

1321280 is an equidigital number, since it uses as much as digits as its factorization.

1321280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4146 (or 4136 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 1321280 is about 1149.4694428300. The cubic root of 1321280 is about 109.7315769292.

The spelling of 1321280 in words is "one million, three hundred twenty-one thousand, two hundred eighty".