1281225600 has 240 divisors, whose sum is σ = 4728960720. Its totient is φ = 341591040.

The previous prime is 1281225581. The next prime is 1281225607. The reversal of 1281225600 is 65221821.

It is a happy number.

1281225600 is a `hidden beast` number, since 1 + 2 + 81 + 22 + 560 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1281225607) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 256729 + ... + 261671.

It is an arithmetic number, because the mean of its divisors is an integer number (19704003).

Almost surely, 2^1281225600 is an apocalyptic number.

1281225600 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 1281225600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2364480360).

1281225600 is an abundant number, since it is smaller than the sum of its proper divisors (3447735120).

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

1281225600 is an equidigital number, since it uses as much as digits as its factorization.

1281225600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4979 (or 4953 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 1281225600 is about 35794.2118225838. The cubic root of 1281225600 is about 1086.1134767416.

The spelling of 1281225600 in words is "one billion, two hundred eighty-one million, two hundred twenty-five thousand, six hundred".