1321001242040 has 128 divisors (see below), whose sum is σ = 3186733536000. Its totient is φ = 491329317888.

The previous prime is 1321001242013. The next prime is 1321001242051. The reversal of 1321001242040 is 402421001231.

It is a Harshad number since it is a multiple of its sum of digits (20).

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, 28809212 + ... + 28855028.

It is an arithmetic number, because the mean of its divisors is an integer number (24896355750).

Almost surely, 2^{1321001242040} is an apocalyptic number.

1321001242040 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 1321001242040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1593366768000).

1321001242040 is an abundant number, since it is smaller than the sum of its proper divisors (1865732293960).

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

1321001242040 is a wasteful number, since it uses less digits than its factorization.

1321001242040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46549 (or 46545 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 1321001242040 its reverse (402421001231), we get a palindrome (1723422243271).

The spelling of 1321001242040 in words is "one trillion, three hundred twenty-one billion, one million, two hundred forty-two thousand, forty".