844385931647 has 2 divisors, whose sum is σ = 844385931648. Its totient is φ = 844385931646.

The previous prime is 844385931619. The next prime is 844385931667. The reversal of 844385931647 is 746139583448.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 844385931647 - 2¹⁶ = 844385866111 is a prime.

It is a super-2 number, since 2×844385931647² (a number of 25 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 844385931647.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (844385931617) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 422192965823 + 422192965824.

It is an arithmetic number, because the mean of its divisors is an integer number (422192965824).

Almost surely, 2^844385931647 is an apocalyptic number.

844385931647 is a deficient number, since it is larger than the sum of its proper divisors (1).

844385931647 is an equidigital number, since it uses as much as digits as its factorization.

844385931647 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 69672960, while the sum is 62.

The spelling of 844385931647 in words is "eight hundred forty-four billion, three hundred eighty-five million, nine hundred thirty-one thousand, six hundred forty-seven".