810641940 has 144 divisors (see below), whose sum is σ = 2486344896. Its totient is φ = 196654080.

The previous prime is 810641929. The next prime is 810642073. The reversal of 810641940 is 49146018.

It is a congruent number.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 979807 + ... + 980633.

It is an arithmetic number, because the mean of its divisors is an integer number (17266284).

Almost surely, 2^810641940 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 810641940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1243172448).

810641940 is an abundant number, since it is smaller than the sum of its proper divisors (1675702956).

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

810641940 is a wasteful number, since it uses less digits than its factorization.

810641940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 918 (or 885 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 33.

The square root of 810641940 is about 28471.7744441754. The cubic root of 810641940 is about 932.4159406914.

Adding to 810641940 its reverse (49146018), we get a palindrome (859787958).

The spelling of 810641940 in words is "eight hundred ten million, six hundred forty-one thousand, nine hundred forty".