1243989872640 has 312 divisors, whose sum is σ = 4328914733208. Its totient is φ = 330427269120.

The previous prime is 1243989872599. The next prime is 1243989872693. The reversal of 1243989872640 is 462789893421.

1243989872640 is a `hidden beast` number, since 1 + 2 + 439 + 8 + 98 + 72 + 6 + 40 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 107667984384 + 1136321888256 = 328128^2 + 1065984^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 47357110 + ... + 47383370.

It is an arithmetic number, because the mean of its divisors is an integer number (13874726709).

Almost surely, 2^{1243989872640} is an apocalyptic number.

1243989872640 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 1243989872640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2164457366604).

1243989872640 is an abundant number, since it is smaller than the sum of its proper divisors (3084924860568).

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

1243989872640 is a wasteful number, since it uses less digits than its factorization.

1243989872640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26553 (or 26528 counting only the distinct ones).

The product of its (nonzero) digits is 41803776, while the sum is 63.

The spelling of 1243989872640 in words is "one trillion, two hundred forty-three billion, nine hundred eighty-nine million, eight hundred seventy-two thousand, six hundred forty".