811880640 has 336 divisors, whose sum is σ = 3026481120. Its totient is φ = 199065600.

The previous prime is 811880639. The next prime is 811880681. The reversal of 811880640 is 46088118.

811880640 is a `hidden beast` number, since 8 + 1 + 1 + 8 + 8 + 0 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 811880595 and 811880604.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2024440 + ... + 2024840.

Almost surely, 2^811880640 is an apocalyptic number.

811880640 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 811880640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1513240560).

811880640 is an abundant number, since it is smaller than the sum of its proper divisors (2214600480).

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

811880640 is a wasteful number, since it uses less digits than its factorization.

811880640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 480 (or 467 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 36.

The square root of 811880640 is about 28493.5192631588. The cubic root of 811880640 is about 932.8906245099.

The spelling of 811880640 in words is "eight hundred eleven million, eight hundred eighty thousand, six hundred forty".