1281388 has 12 divisors (see below), whose sum is σ = 2250360. Its totient is φ = 638432.

The previous prime is 1281383. The next prime is 1281389. The reversal of 1281388 is 8831821.

It is not an unprimeable number, because it can be changed into a prime (1281383) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1968 + ... + 2536.

It is an arithmetic number, because the mean of its divisors is an integer number (187530).

2^1281388 is an apocalyptic number.

It is an amenable number.

1281388 is a deficient number, since it is larger than the sum of its proper divisors (968972).

1281388 is a wasteful number, since it uses less digits than its factorization.

1281388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1136 (or 1134 counting only the distinct ones).

The product of its digits is 3072, while the sum is 31.

The square root of 1281388 is about 1131.9840988282. The cubic root of 1281388 is about 108.6159364413.

The spelling of 1281388 in words is "one million, two hundred eighty-one thousand, three hundred eighty-eight".