811789440 has 768 divisors, whose sum is σ = 3607372800. Its totient is φ = 150405120.

The previous prime is 811789427. The next prime is 811789441. The reversal of 811789440 is 44987118.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 811789392 and 811789401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (811789441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 42725751 + ... + 42725769.

It is an arithmetic number, because the mean of its divisors is an integer number (4697100).

Almost surely, 2^811789440 is an apocalyptic number.

811789440 is a gapful number since it is divisible by the number (80) 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 811789440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1803686400).

811789440 is an abundant number, since it is smaller than the sum of its proper divisors (2795583360).

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

811789440 is a wasteful number, since it uses less digits than its factorization.

811789440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93 (or 64 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 42.

The square root of 811789440 is about 28491.9188542997. The cubic root of 811789440 is about 932.8556921127.

The spelling of 811789440 in words is "eight hundred eleven million, seven hundred eighty-nine thousand, four hundred forty".