840113617381 has 2 divisors, whose sum is σ = 840113617382. Its totient is φ = 840113617380.

The previous prime is 840113617379. The next prime is 840113617397. The reversal of 840113617381 is 183716311048.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 679897544481 + 160216072900 = 824559^2 + 400270^2 .

It is a cyclic number.

It is not a de Polignac number, because 840113617381 - 2¹ = 840113617379 is a prime.

It is a super-4 number, since 4×840113617381⁴ (a number of 49 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

Together with 840113617379, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (840113617351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 420056808690 + 420056808691.

It is an arithmetic number, because the mean of its divisors is an integer number (420056808691).

Almost surely, 2^840113617381 is an apocalyptic number.

It is an amenable number.

840113617381 is a deficient number, since it is larger than the sum of its proper divisors (1).

840113617381 is an equidigital number, since it uses as much as digits as its factorization.

840113617381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96768, while the sum is 43.

The spelling of 840113617381 in words is "eight hundred forty billion, one hundred thirteen million, six hundred seventeen thousand, three hundred eighty-one".