1220436 has 72 divisors (see below), whose sum is σ = 3669120. Its totient is φ = 334656.

The previous prime is 1220423. The next prime is 1220437. The reversal of 1220436 is 6340221.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a d-powerful number, because it can be written as 1 + 2¹⁵ + 2¹⁷ + 0 + 4¹⁰ + 3⁵ + 6⁵ .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220437) 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 23 ways as a sum of consecutive naturals, for example, 7225 + ... + 7391.

It is an arithmetic number, because the mean of its divisors is an integer number (50960).

2^1220436 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1220436, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1834560).

1220436 is an abundant number, since it is smaller than the sum of its proper divisors (2448684).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1220436 is a wasteful number, since it uses less digits than its factorization.

1220436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213 (or 208 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 1220436 is about 1104.7334520146. The cubic root of 1220436 is about 106.8657004322.

Adding to 1220436 its reverse (6340221), we get a palindrome (7560657).

The spelling of 1220436 in words is "one million, two hundred twenty thousand, four hundred thirty-six".