1281399 has 24 divisors (see below), whose sum is σ = 2079360. Its totient is φ = 698544.

The previous prime is 1281389. The next prime is 1281407. The reversal of 1281399 is 9931821.

It is not a de Polignac number, because 1281399 - 2⁴ = 1281383 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1281349) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3192 + ... + 3570.

It is an arithmetic number, because the mean of its divisors is an integer number (86640).

2^1281399 is an apocalyptic number.

1281399 is a deficient number, since it is larger than the sum of its proper divisors (797961).

1281399 is a wasteful number, since it uses less digits than its factorization.

1281399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 419 (or 412 counting only the distinct ones).

The product of its digits is 3888, while the sum is 33.

The square root of 1281399 is about 1131.9889575433. The cubic root of 1281399 is about 108.6162472428.

The spelling of 1281399 in words is "one million, two hundred eighty-one thousand, three hundred ninety-nine".