6811215840 has 864 divisors, whose sum is σ = 28693986048. Its totient is φ = 1459814400.

The previous prime is 6811215839. The next prime is 6811215841. The reversal of 6811215840 is 485121186.

6811215840 is a `hidden beast` number, since 68 + 1 + 12 + 1 + 584 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (6811215839) and next prime (6811215841).

It is a super-2 number, since 2×6811215840² = 92785322438133811200, which contains 22 as substring.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

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 = 6811215795 and 6811215804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6811215841) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 70218672 + ... + 70218768.

It is an arithmetic number, because the mean of its divisors is an integer number (33210632).

Almost surely, 2^6811215840 is an apocalyptic number.

6811215840 is a gapful number since it is divisible by the number (60) 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 6811215840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14346993024).

6811215840 is an abundant number, since it is smaller than the sum of its proper divisors (21882770208).

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

6811215840 is a wasteful number, since it uses less digits than its factorization.

6811215840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 184 (or 162 counting only the distinct ones).

The product of its (nonzero) digits is 15360, while the sum is 36.

The square root of 6811215840 is about 82530.0905124913. The cubic root of 6811215840 is about 1895.5775109477.

The spelling of 6811215840 in words is "six billion, eight hundred eleven million, two hundred fifteen thousand, eight hundred forty".