1331009280 has 288 divisors, whose sum is σ = 4974278400. Its totient is φ = 336089088.

The previous prime is 1331009249. The next prime is 1331009291. The reversal of 1331009280 is 829001331.

It is a tau number, because it is divible by the number of its divisors (288).

It is a super-2 number, since 2×1331009280² = 3543171406892236800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 655627 + ... + 657653.

It is an arithmetic number, because the mean of its divisors is an integer number (17271800).

Almost surely, 2^1331009280 is an apocalyptic number.

1331009280 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 1331009280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2487139200).

1331009280 is an abundant number, since it is smaller than the sum of its proper divisors (3643269120).

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

1331009280 is a wasteful number, since it uses less digits than its factorization.

1331009280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2076 (or 2056 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 1331009280 is about 36482.9998766549. Note that the first 3 decimals coincide. The cubic root of 1331009280 is about 1100.0025564679.

The spelling of 1331009280 in words is "one billion, three hundred thirty-one million, nine thousand, two hundred eighty".