1280966400 has 540 divisors, whose sum is σ = 5428267152. Its totient is φ = 291962880.

The previous prime is 1280966399. The next prime is 1280966411. The reversal of 1280966400 is 46690821.

1280966400 is a `hidden beast` number, since 1 + 2 + 8 + 0 + 9 + 6 + 640 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (540).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 3628624 + ... + 3628976.

Almost surely, 2^1280966400 is an apocalyptic number.

1280966400 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 1280966400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2714133576).

1280966400 is an abundant number, since it is smaller than the sum of its proper divisors (4147300752).

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

1280966400 is an equidigital number, since it uses as much as digits as its factorization.

1280966400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 398 (or 370 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 1280966400 is about 35790.5909423133. The cubic root of 1280966400 is about 1086.0402292719.

The spelling of 1280966400 in words is "one billion, two hundred eighty million, nine hundred sixty-six thousand, four hundred".