1220344021 has 4 divisors (see below), whose sum is σ = 1314216652. Its totient is φ = 1126471392.

The previous prime is 1220344019. The next prime is 1220344067. The reversal of 1220344021 is 1204430221.

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 192820996 + 1027523025 = 13886^2 + 32055^2 .

It is a cyclic number.

It is not a de Polignac number, because 1220344021 - 2¹ = 1220344019 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 1220344021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220344421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46936296 + ... + 46936321.

It is an arithmetic number, because the mean of its divisors is an integer number (328554163).

Almost surely, 2^1220344021 is an apocalyptic number.

It is an amenable number.

1220344021 is a deficient number, since it is larger than the sum of its proper divisors (93872631).

1220344021 is an equidigital number, since it uses as much as digits as its factorization.

1220344021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93872630.

The product of its (nonzero) digits is 384, while the sum is 19.

The square root of 1220344021 is about 34933.4226923157. The cubic root of 1220344021 is about 1068.6301569575.

Adding to 1220344021 its reverse (1204430221), we get a palindrome (2424774242).

The spelling of 1220344021 in words is "one billion, two hundred twenty million, three hundred forty-four thousand, twenty-one".