1280280 has 64 divisors (see below), whose sum is σ = 3939840. Its totient is φ = 332672.

The previous prime is 1280267. The next prime is 1280281. The reversal of 1280280 is 820821.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1280281) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5527 + ... + 5753.

It is an arithmetic number, because the mean of its divisors is an integer number (61560).

2^1280280 is an apocalyptic number.

1280280 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 1280280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1969920).

1280280 is an abundant number, since it is smaller than the sum of its proper divisors (2659560).

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

1280280 is a wasteful number, since it uses less digits than its factorization.

1280280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 288 (or 284 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 21.

The square root of 1280280 is about 1131.4945868187. The cubic root of 1280280 is about 108.5846211380.

The spelling of 1280280 in words is "one million, two hundred eighty thousand, two hundred eighty".