1012221220 has 48 divisors (see below), whose sum is σ = 2208855600. Its totient is φ = 389168640.

The previous prime is 1012221211. The next prime is 1012221229. The reversal of 1012221220 is 221222101.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1012221211) and next prime (1012221229).

It can be written as a sum of positive squares in 8 ways, for example, as 169364196 + 842857024 = 13014^2 + 29032^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1012221220.

It is not an unprimeable number, because it can be changed into a prime (1012221229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 129010 + ... + 136630.

It is an arithmetic number, because the mean of its divisors is an integer number (46017825).

Almost surely, 2^1012221220 is an apocalyptic number.

1012221220 is a gapful number since it is divisible by the number (10) 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 1012221220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1104427800).

1012221220 is an abundant number, since it is smaller than the sum of its proper divisors (1196634380).

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

1012221220 is a wasteful number, since it uses less digits than its factorization.

1012221220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7888 (or 7886 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 1012221220 is about 31815.4242467392. The cubic root of 1012221220 is about 1004.0572564078.

Adding to 1012221220 its reverse (221222101), we get a palindrome (1233443321).

The spelling of 1012221220 in words is "one billion, twelve million, two hundred twenty-one thousand, two hundred twenty".