1281984 has 56 divisors (see below), whose sum is σ = 3706368. Its totient is φ = 387840.

The previous prime is 1281983. The next prime is 1282007. The reversal of 1281984 is 4891821.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1281983) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1809 + ... + 2415.

2^1281984 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 1281984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1853184).

1281984 is an abundant number, since it is smaller than the sum of its proper divisors (2424384).

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

1281984 is a wasteful number, since it uses less digits than its factorization.

1281984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 633 (or 623 counting only the distinct ones).

The product of its digits is 4608, while the sum is 33.

The square root of 1281984 is about 1132.2473228054. The cubic root of 1281984 is about 108.6327736689.

It can be divided in two parts, 128 and 1984, that added together give a palindrome (2112).

The spelling of 1281984 in words is "one million, two hundred eighty-one thousand, nine hundred eighty-four".