1220251440 has 160 divisors (see below), whose sum is σ = 4039027200. Its totient is φ = 303851520.

The previous prime is 1220251423. The next prime is 1220251447. The reversal of 1220251440 is 441520221.

It is not an unprimeable number, because it can be changed into a prime (1220251447) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 321876 + ... + 325644.

It is an arithmetic number, because the mean of its divisors is an integer number (25243920).

Almost surely, 2^1220251440 is an apocalyptic number.

1220251440 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 1220251440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2019513600).

1220251440 is an abundant number, since it is smaller than the sum of its proper divisors (2818775760).

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

1220251440 is a wasteful number, since it uses less digits than its factorization.

1220251440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3875 (or 3869 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 21.

The square root of 1220251440 is about 34932.0975608394. The cubic root of 1220251440 is about 1068.6031325150.

Adding to 1220251440 its reverse (441520221), we get a palindrome (1661771661).

The spelling of 1220251440 in words is "one billion, two hundred twenty million, two hundred fifty-one thousand, four hundred forty".