1221285 has 16 divisors (see below), whose sum is σ = 2104704. Its totient is φ = 601152.

The previous prime is 1221251. The next prime is 1221289. The reversal of 1221285 is 5821221.

It is a happy number.

It is not a de Polignac number, because 1221285 - 2⁶ = 1221221 is a prime.

It is an Ulam number.

It is a Curzon number.

1221285 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221289) 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, 2937 + ... + 3326.

It is an arithmetic number, because the mean of its divisors is an integer number (131544).

2^1221285 is an apocalyptic number.

1221285 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1221285 is a deficient number, since it is larger than the sum of its proper divisors (883419).

1221285 is a wasteful number, since it uses less digits than its factorization.

1221285 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6284.

The product of its digits is 320, while the sum is 21.

The square root of 1221285 is about 1105.1176407967. The cubic root of 1221285 is about 106.8904751710.

The spelling of 1221285 in words is "one million, two hundred twenty-one thousand, two hundred eighty-five".