811388844 has 216 divisors, whose sum is σ = 2574411840. Its totient is φ = 214135488.

The previous prime is 811388813. The next prime is 811388861. The reversal of 811388844 is 448883118.

It is a self number, because there is not a number n which added to its sum of digits gives 811388844.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1440907 + ... + 1441469.

Almost surely, 2^811388844 is an apocalyptic number.

811388844 is a gapful number since it is divisible by the number (84) 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 811388844, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1287205920).

811388844 is an abundant number, since it is smaller than the sum of its proper divisors (1763022996).

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

811388844 is a wasteful number, since it uses less digits than its factorization.

811388844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 649 (or 637 counting only the distinct ones).

The product of its digits is 196608, while the sum is 45.

The square root of 811388844 is about 28484.8879934607. The cubic root of 811388844 is about 932.7022205648.

The spelling of 811388844 in words is "eight hundred eleven million, three hundred eighty-eight thousand, eight hundred forty-four".