1281026880 has 448 divisors, whose sum is σ = 5266944000. Its totient is φ = 287041536.

The previous prime is 1281026809. The next prime is 1281026881. The reversal of 1281026880 is 886201821.

It is a tau number, because it is divible by the number of its divisors (448).

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 (1281026881) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3568141 + ... + 3568499.

Almost surely, 2^1281026880 is an apocalyptic number.

1281026880 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 1281026880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2633472000).

1281026880 is an abundant number, since it is smaller than the sum of its proper divisors (3985917120).

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

1281026880 is a wasteful number, since it uses less digits than its factorization.

1281026880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 451 (or 435 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 36.

The square root of 1281026880 is about 35791.4358471409. The cubic root of 1281026880 is about 1086.0573212319.

The spelling of 1281026880 in words is "one billion, two hundred eighty-one million, twenty-six thousand, eight hundred eighty".