1221030252 has 72 divisors (see below), whose sum is σ = 3380329680. Its totient is φ = 369325440.

The previous prime is 1221030199. The next prime is 1221030257. The reversal of 1221030252 is 2520301221.

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

It is not an unprimeable number, because it can be changed into a prime (1221030257) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5502 + ... + 49722.

Almost surely, 2^1221030252 is an apocalyptic number.

1221030252 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221030252, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1690164840).

1221030252 is an abundant number, since it is smaller than the sum of its proper divisors (2159299428).

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

1221030252 is a wasteful number, since it uses less digits than its factorization.

1221030252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44303 (or 44298 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 1221030252 is about 34943.2432953783. The cubic root of 1221030252 is about 1068.8304255471.

Adding to 1221030252 its reverse (2520301221), we get a palindrome (3741331473).

The spelling of 1221030252 in words is "one billion, two hundred twenty-one million, thirty thousand, two hundred fifty-two".