844406511381 has 12 divisors (see below), whose sum is σ = 1220271219180. Its totient is φ = 562673247360.

The previous prime is 844406511367. The next prime is 844406511383. The reversal of 844406511381 is 183115604448.

844406511381 is a `hidden beast` number, since 84 + 440 + 6 + 51 + 1 + 3 + 81 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 610639096356 + 233767415025 = 781434^2 + 483495^2 .

It is not a de Polignac number, because 844406511381 - 2⁵ = 844406511349 is a prime.

It is a super-2 number, since 2×844406511381² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (844406511383) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 22015350 + ... + 22053671.

It is an arithmetic number, because the mean of its divisors is an integer number (101689268265).

Almost surely, 2^844406511381 is an apocalyptic number.

It is an amenable number.

844406511381 is a deficient number, since it is larger than the sum of its proper divisors (375864707799).

844406511381 is a wasteful number, since it uses less digits than its factorization.

844406511381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44071156 (or 44071153 counting only the distinct ones).

The product of its (nonzero) digits is 368640, while the sum is 45.

The spelling of 844406511381 in words is "eight hundred forty-four billion, four hundred six million, five hundred eleven thousand, three hundred eighty-one".