1281212856 has 384 divisors, whose sum is σ = 4596480000. Its totient is φ = 323516160.

The previous prime is 1281212839. The next prime is 1281212897. The reversal of 1281212856 is 6582121821.

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

Its product of digits (15360) is a multiple of the sum of its prime factors (240).

It is a self number, because there is not a number n which added to its sum of digits gives 1281212856.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 8598670 + ... + 8598818.

It is an arithmetic number, because the mean of its divisors is an integer number (11970000).

Almost surely, 2^1281212856 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1281212856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2298240000).

1281212856 is an abundant number, since it is smaller than the sum of its proper divisors (3315267144).

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

1281212856 is a wasteful number, since it uses less digits than its factorization.

1281212856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 240 (or 219 counting only the distinct ones).

The product of its digits is 15360, while the sum is 36.

The square root of 1281212856 is about 35794.0338045323. The cubic root of 1281212856 is about 1086.1098756386.

The spelling of 1281212856 in words is "one billion, two hundred eighty-one million, two hundred twelve thousand, eight hundred fifty-six".