1263221 has 4 divisors (see below), whose sum is σ = 1265772. Its totient is φ = 1260672.

The previous prime is 1263209. The next prime is 1263239. The reversal of 1263221 is 1223621.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 600625 + 662596 = 775^2 + 814^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1263221 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1263221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1263121) 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, 266 + ... + 1611.

It is an arithmetic number, because the mean of its divisors is an integer number (316443).

2^1263221 is an apocalyptic number.

It is an amenable number.

1263221 is a deficient number, since it is larger than the sum of its proper divisors (2551).

1263221 is an equidigital number, since it uses as much as digits as its factorization.

1263221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2550.

The product of its digits is 144, while the sum is 17.

The square root of 1263221 is about 1123.9310477071. The cubic root of 1263221 is about 108.1001870959.

Adding to 1263221 its reverse (1223621), we get a palindrome (2486842).

The spelling of 1263221 in words is "one million, two hundred sixty-three thousand, two hundred twenty-one".