687942249786 has 192 divisors, whose sum is σ = 1682171487360. Its totient is φ = 201360453120.

The previous prime is 687942249779. The next prime is 687942249809.

687942249786 is a `hidden beast` number, since 6 + 87 + 9 + 422 + 49 + 7 + 86 = 666.

687942249786 is nontrivially palindromic in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 806496936 + ... + 806497788.

It is an arithmetic number, because the mean of its divisors is an integer number (8761309830).

Almost surely, 2^687942249786 is an apocalyptic number.

687942249786 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 687942249786, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (841085743680).

687942249786 is an abundant number, since it is smaller than the sum of its proper divisors (994229237574).

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

687942249786 is a wasteful number, since it uses less digits than its factorization.

687942249786 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1581 (or 1578 counting only the distinct ones).

The product of its digits is 585252864, while the sum is 72.

The spelling of 687942249786 in words is "six hundred eighty-seven billion, nine hundred forty-two million, two hundred forty-nine thousand, seven hundred eighty-six".