811543940 has 48 divisors (see below), whose sum is σ = 1758313200. Its totient is φ = 314399232.

The previous prime is 811543927. The next prime is 811543951. The reversal of 811543940 is 49345118.

It can be written as a sum of positive squares in 8 ways, for example, as 19909444 + 791634496 = 4462^2 + 28136^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 811543940.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 167066 + ... + 171854.

It is an arithmetic number, because the mean of its divisors is an integer number (36631525).

Almost surely, 2^811543940 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 811543940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (879156600).

811543940 is an abundant number, since it is smaller than the sum of its proper divisors (946769260).

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

811543940 is a wasteful number, since it uses less digits than its factorization.

811543940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5064 (or 5062 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 35.

The square root of 811543940 is about 28487.6102893872. The cubic root of 811543940 is about 932.7616450806.

The spelling of 811543940 in words is "eight hundred eleven million, five hundred forty-three thousand, nine hundred forty".