688735921040 has 160 divisors (see below), whose sum is σ = 1633800430080. Its totient is φ = 269973504000.

The previous prime is 688735921009. The next prime is 688735921079. The reversal of 688735921040 is 40129537886.

It is a super-2 number, since 2×688735921040² (a number of 24 digits) contains 22 as substring.

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 31 ways as a sum of consecutive naturals, for example, 455813885 + ... + 455815395.

It is an arithmetic number, because the mean of its divisors is an integer number (10211252688).

It is a 1-persistent number, because it is pandigital, but 2⋅688735921040 = 1377471842080 is not.

Almost surely, 2^688735921040 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 688735921040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (816900215040).

688735921040 is an abundant number, since it is smaller than the sum of its proper divisors (945064509040).

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

688735921040 is a wasteful number, since it uses less digits than its factorization.

688735921040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2161 (or 2155 counting only the distinct ones).

The product of its (nonzero) digits is 2903040, while the sum is 53.

The spelling of 688735921040 in words is "six hundred eighty-eight billion, seven hundred thirty-five million, nine hundred twenty-one thousand, forty".