6687346778385 has 576 divisors, whose sum is σ = 15324687302400. Its totient is φ = 2452859781120.

The previous prime is 6687346778311. The next prime is 6687346778407. The reversal of 6687346778385 is 5838776437866.

It is not a de Polignac number, because 6687346778385 - 2¹¹ = 6687346776337 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6687346778385.

It is an unprimeable number.

It is a polite number, since it can be written in 575 ways as a sum of consecutive naturals, for example, 5188010821 + ... + 5188012109.

It is an arithmetic number, because the mean of its divisors is an integer number (26605359900).

Almost surely, 2^{6687346778385} is an apocalyptic number.

6687346778385 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

6687346778385 is an abundant number, since it is smaller than the sum of its proper divisors (8637340524015).

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

6687346778385 is a wasteful number, since it uses less digits than its factorization.

6687346778385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1442 (or 1394 counting only the distinct ones).

The product of its digits is 6827950080, while the sum is 78.

The spelling of 6687346778385 in words is "six trillion, six hundred eighty-seven billion, three hundred forty-six million, seven hundred seventy-eight thousand, three hundred eighty-five".