811326640 has 20 divisors (see below), whose sum is σ = 1886334624. Its totient is φ = 324530624.

The previous prime is 811326631. The next prime is 811326647. The reversal of 811326640 is 46623118.

It is a happy number.

811326640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (20).

It is not an unprimeable number, because it can be changed into a prime (811326647) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5070712 + ... + 5070871.

Almost surely, 2^811326640 is an apocalyptic number.

811326640 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

811326640 is an abundant number, since it is smaller than the sum of its proper divisors (1075007984).

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

811326640 is a wasteful number, since it uses less digits than its factorization.

811326640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10141596 (or 10141590 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 31.

The square root of 811326640 is about 28483.7960953241. The cubic root of 811326640 is about 932.6783851818.

Adding to 811326640 its reverse (46623118), we get a palindrome (857949758).

The spelling of 811326640 in words is "eight hundred eleven million, three hundred twenty-six thousand, six hundred forty".