687898398942 has 12 divisors (see below), whose sum is σ = 1490446531080. Its totient is φ = 229299466308.

The previous prime is 687898398871. The next prime is 687898398953. The reversal of 687898398942 is 249893898786.

687898398942 is a `hidden beast` number, since 68 + 7 + 89 + 8 + 398 + 94 + 2 = 666.

It is a congruent number.

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 5 ways as a sum of consecutive naturals, for example, 19108288842 + ... + 19108288877.

It is an arithmetic number, because the mean of its divisors is an integer number (124203877590).

Almost surely, 2^687898398942 is an apocalyptic number.

687898398942 is an abundant number, since it is smaller than the sum of its proper divisors (802548132138).

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

687898398942 is a wasteful number, since it uses less digits than its factorization.

687898398942 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38216577727 (or 38216577724 counting only the distinct ones).

The product of its digits is 3009871872, while the sum is 81.

The spelling of 687898398942 in words is "six hundred eighty-seven billion, eight hundred ninety-eight million, three hundred ninety-eight thousand, nine hundred forty-two".