2391821818144 has 72 divisors (see below), whose sum is σ = 5178670745724. Its totient is φ = 1086609216000.

The previous prime is 2391821818121. The next prime is 2391821818147. The reversal of 2391821818144 is 4418181281932.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 2241044928144 + 150776890000 = 1497012^2 + 388300^2 .

It is a junction number, because it is equal to n+sod(n) for n = 2391821818091 and 2391821818100.

It is not an unprimeable number, because it can be changed into a prime (2391821818147) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7103194 + ... + 7432294.

Almost surely, 2^{2391821818144} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2391821818144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2589335372862).

2391821818144 is an abundant number, since it is smaller than the sum of its proper divisors (2786848927580).

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

2391821818144 is a wasteful number, since it uses less digits than its factorization.

2391821818144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 331010 (or 330991 counting only the distinct ones).

The product of its digits is 884736, while the sum is 52.

The spelling of 2391821818144 in words is "two trillion, three hundred ninety-one billion, eight hundred twenty-one million, eight hundred eighteen thousand, one hundred forty-four".