1285221 has 16 divisors (see below), whose sum is σ = 2000000. Its totient is φ = 733824.

The previous prime is 1285213. The next prime is 1285223. The reversal of 1285221 is 1225821.

It is a happy number.

It is not a de Polignac number, because 1285221 - 2³ = 1285213 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1285223) 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 15 ways as a sum of consecutive naturals, for example, 405 + ... + 1653.

It is an arithmetic number, because the mean of its divisors is an integer number (125000).

2^1285221 is an apocalyptic number.

It is an amenable number.

1285221 is a deficient number, since it is larger than the sum of its proper divisors (714779).

1285221 is an equidigital number, since it uses as much as digits as its factorization.

1285221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1273 (or 1259 counting only the distinct ones).

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

The square root of 1285221 is about 1133.6758796058. The cubic root of 1285221 is about 108.7241291347.

The spelling of 1285221 in words is "one million, two hundred eighty-five thousand, two hundred twenty-one".