1243315440 has 320 divisors, whose sum is σ = 4505425920. Its totient is φ = 314772480.

The previous prime is 1243315433. The next prime is 1243315441. The reversal of 1243315440 is 445133421.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1243315441) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3756075 + ... + 3756405.

It is an arithmetic number, because the mean of its divisors is an integer number (14079456).

Almost surely, 2^1243315440 is an apocalyptic number.

1243315440 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 1243315440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2252712960).

1243315440 is an abundant number, since it is smaller than the sum of its proper divisors (3262110480).

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

1243315440 is a wasteful number, since it uses less digits than its factorization.

1243315440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 437 (or 425 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 1243315440 is about 35260.6783825836. The cubic root of 1243315440 is about 1075.2937189115.

Adding to 1243315440 its reverse (445133421), we get a palindrome (1688448861).

The spelling of 1243315440 in words is "one billion, two hundred forty-three million, three hundred fifteen thousand, four hundred forty".