1221303 has 8 divisors (see below), whose sum is σ = 1639408. Its totient is φ = 808704.

The previous prime is 1221299. The next prime is 1221373. The reversal of 1221303 is 3031221.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1221303 - 2² = 1221299 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221373) 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 7 ways as a sum of consecutive naturals, for example, 826 + ... + 1767.

It is an arithmetic number, because the mean of its divisors is an integer number (204926).

2^1221303 is an apocalyptic number.

1221303 is a deficient number, since it is larger than the sum of its proper divisors (418105).

1221303 is a wasteful number, since it uses less digits than its factorization.

1221303 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2753.

The product of its (nonzero) digits is 36, while the sum is 12.

The square root of 1221303 is about 1105.1257846960. The cubic root of 1221303 is about 106.8910003062.

Adding to 1221303 its reverse (3031221), we get a palindrome (4252524).

It can be divided in two parts, 1221 and 303, that multiplied together give a palindrome (369963).

The spelling of 1221303 in words is "one million, two hundred twenty-one thousand, three hundred three".