1244155220 has 96 divisors (see below), whose sum is σ = 3272693760. Its totient is φ = 385971840.

The previous prime is 1244155219. The next prime is 1244155259. The reversal of 1244155220 is 225514421.

It is a super-2 number, since 2×1244155220² = 3095844422906496800, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1244155220.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 347801 + ... + 351359.

It is an arithmetic number, because the mean of its divisors is an integer number (34090560).

Almost surely, 2^1244155220 is an apocalyptic number.

1244155220 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 1244155220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1636346880).

1244155220 is an abundant number, since it is smaller than the sum of its proper divisors (2028538540).

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

1244155220 is a wasteful number, since it uses less digits than its factorization.

1244155220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3813 (or 3811 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 26.

The square root of 1244155220 is about 35272.5845381367. The cubic root of 1244155220 is about 1075.5357617855.

Adding to 1244155220 its reverse (225514421), we get a palindrome (1469669641).

The spelling of 1244155220 in words is "one billion, two hundred forty-four million, one hundred fifty-five thousand, two hundred twenty".