1243780740 has 144 divisors (see below), whose sum is σ = 3903943680. Its totient is φ = 320336640.

The previous prime is 1243780687. The next prime is 1243780751. The reversal of 1243780740 is 470873421.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1243780695 and 1243780704.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 667410 + ... + 669270.

It is an arithmetic number, because the mean of its divisors is an integer number (27110720).

Almost surely, 2^1243780740 is an apocalyptic number.

1243780740 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 1243780740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1951971840).

1243780740 is an abundant number, since it is smaller than the sum of its proper divisors (2660162940).

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

1243780740 is a wasteful number, since it uses less digits than its factorization.

1243780740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2002 (or 1997 counting only the distinct ones).

The product of its (nonzero) digits is 37632, while the sum is 36.

The square root of 1243780740 is about 35267.2757666367. The cubic root of 1243780740 is about 1075.4278419584.

The spelling of 1243780740 in words is "one billion, two hundred forty-three million, seven hundred eighty thousand, seven hundred forty".