1281285 has 16 divisors (see below), whose sum is σ = 2278080. Its totient is φ = 683280.

The previous prime is 1281283. The next prime is 1281317. The reversal of 1281285 is 5821821.

It is not a de Polignac number, because 1281285 - 2¹ = 1281283 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1281281) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4611 + ... + 4880.

It is an arithmetic number, because the mean of its divisors is an integer number (142380).

2^1281285 is an apocalyptic number.

1281285 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1281285 is a deficient number, since it is larger than the sum of its proper divisors (996795).

1281285 is an equidigital number, since it uses as much as digits as its factorization.

1281285 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9505 (or 9499 counting only the distinct ones).

The product of its digits is 1280, while the sum is 27.

The square root of 1281285 is about 1131.9386025752. The cubic root of 1281285 is about 108.6130261229.

It can be divided in two parts, 1281 and 285, that multiplied together give a triangular number (365085 = T₈₅₄).

The spelling of 1281285 in words is "one million, two hundred eighty-one thousand, two hundred eighty-five".