688021503813 has 32 divisors (see below), whose sum is σ = 1164944697600. Its totient is φ = 393141454848.

The previous prime is 688021503739. The next prime is 688021503853. The reversal of 688021503813 is 318305120886.

688021503813 is a `hidden beast` number, since 68 + 8 + 0 + 2 + 1 + 503 + 81 + 3 = 666.

It is not a de Polignac number, because 688021503813 - 2¹² = 688021499717 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688021503853) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8268745 + ... + 8351537.

It is an arithmetic number, because the mean of its divisors is an integer number (36404521800).

Almost surely, 2^688021503813 is an apocalyptic number.

688021503813 is a gapful number since it is divisible by the number (63) formed by its first and last digit.

It is an amenable number.

688021503813 is a deficient number, since it is larger than the sum of its proper divisors (476923193787).

688021503813 is a wasteful number, since it uses less digits than its factorization.

688021503813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126778 (or 126772 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 45.

The spelling of 688021503813 in words is "six hundred eighty-eight billion, twenty-one million, five hundred three thousand, eight hundred thirteen".