688121886 has 16 divisors (see below), whose sum is σ = 1457199504. Its totient is φ = 215881344.

The previous prime is 688121881. The next prime is 688121887.

688121886 is nontrivially palindromic in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688121881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3373045 + ... + 3373248.

It is an arithmetic number, because the mean of its divisors is an integer number (91074969).

Almost surely, 2^688121886 is an apocalyptic number.

688121886 is an abundant number, since it is smaller than the sum of its proper divisors (769077618).

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

688121886 is a wasteful number, since it uses less digits than its factorization.

688121886 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6746315.

The product of its digits is 294912, while the sum is 48.

The square root of 688121886 is about 26232.0774244054. The cubic root of 688121886 is about 882.8531217172.

The spelling of 688121886 in words is "six hundred eighty-eight million, one hundred twenty-one thousand, eight hundred eighty-six".