1220605 has 4 divisors (see below), whose sum is σ = 1464732. Its totient is φ = 976480.

The previous prime is 1220599. The next prime is 1220623. The reversal of 1220605 is 5060221.

It is a happy number.

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 662596 + 558009 = 814^2 + 747^2 .

It is not a de Polignac number, because 1220605 - 2¹¹ = 1218557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 122056 + ... + 122065.

It is an arithmetic number, because the mean of its divisors is an integer number (366183).

2^1220605 is an apocalyptic number.

It is an amenable number.

1220605 is a deficient number, since it is larger than the sum of its proper divisors (244127).

1220605 is an equidigital number, since it uses as much as digits as its factorization.

1220605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244126.

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 1220605 is about 1104.8099384057. The cubic root of 1220605 is about 106.8706329508.

Adding to 1220605 its reverse (5060221), we get a palindrome (6280826).

The spelling of 1220605 in words is "one million, two hundred twenty thousand, six hundred five".