6687946440 has 320 divisors, whose sum is σ = 26809263360. Its totient is φ = 1462095360.

The previous prime is 6687946427. The next prime is 6687946453. The reversal of 6687946440 is 446497866.

6687946440 is a `hidden beast` number, since 66 + 87 + 9 + 464 + 40 = 666.

It is an interprime number because it is at equal distance from previous prime (6687946427) and next prime (6687946453).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 515230 + ... + 528050.

It is an arithmetic number, because the mean of its divisors is an integer number (83778948).

Almost surely, 2^6687946440 is an apocalyptic number.

6687946440 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 6687946440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13404631680).

6687946440 is an abundant number, since it is smaller than the sum of its proper divisors (20121316920).

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

6687946440 is a wasteful number, since it uses less digits than its factorization.

6687946440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12874 (or 12861 counting only the distinct ones).

The product of its (nonzero) digits is 6967296, while the sum is 54.

The square root of 6687946440 is about 81779.8657372339. The cubic root of 6687946440 is about 1884.0724342308.

The spelling of 6687946440 in words is "six billion, six hundred eighty-seven million, nine hundred forty-six thousand, four hundred forty".