1280438208 has 168 divisors, whose sum is σ = 4280712800. Its totient is φ = 365783040.

The previous prime is 1280438207. The next prime is 1280438213. The reversal of 1280438208 is 8028340821.

It is a happy number.

1280438208 is a `hidden beast` number, since 12 + 8 + 0 + 438 + 208 = 666.

It is a tau number, because it is divible by the number of its divisors (168).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1280438207) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 194328 + ... + 200808.

Almost surely, 2^1280438208 is an apocalyptic number.

1280438208 is a gapful number since it is divisible by the number (18) 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 1280438208, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2140356400).

1280438208 is an abundant number, since it is smaller than the sum of its proper divisors (3000274592).

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

1280438208 is an equidigital number, since it uses as much as digits as its factorization.

1280438208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6520 (or 6493 counting only the distinct ones).

The product of its (nonzero) digits is 24576, while the sum is 36.

The square root of 1280438208 is about 35783.2112589130. The cubic root of 1280438208 is about 1085.8909366173.

The spelling of 1280438208 in words is "one billion, two hundred eighty million, four hundred thirty-eight thousand, two hundred eight".