1221533 has 2 divisors, whose sum is σ = 1221534. Its totient is φ = 1221532.

The previous prime is 1221527. The next prime is 1221541. The reversal of 1221533 is 3351221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1026169 + 195364 = 1013^2 + 442^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221533 - 2⁶ = 1221469 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221503) 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 as a sum of consecutive naturals, namely, 610766 + 610767.

It is an arithmetic number, because the mean of its divisors is an integer number (610767).

2^1221533 is an apocalyptic number.

It is an amenable number.

1221533 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221533 is an equidigital number, since it uses as much as digits as its factorization.

1221533 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 180, while the sum is 17.

The square root of 1221533 is about 1105.2298403500. The cubic root of 1221533 is about 106.8977099125.

Adding to 1221533 its reverse (3351221), we get a palindrome (4572754).

The spelling of 1221533 in words is "one million, two hundred twenty-one thousand, five hundred thirty-three".