688961853 has 12 divisors (see below), whose sum is σ = 995478588. Its totient is φ = 459164160.

The previous prime is 688961851. The next prime is 688961857. The reversal of 688961853 is 358169886.

It can be written as a sum of positive squares in 2 ways, for example, as 174715524 + 514246329 = 13218^2 + 22677^2 .

It is not a de Polignac number, because 688961853 - 2¹ = 688961851 is a prime.

It is a super-3 number, since 3×688961853³ (a number of 27 digits) contains 333 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 688961853.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688961851) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 24093 + ... + 44253.

It is an arithmetic number, because the mean of its divisors is an integer number (82956549).

Almost surely, 2^688961853 is an apocalyptic number.

It is an amenable number.

688961853 is a deficient number, since it is larger than the sum of its proper divisors (306516735).

688961853 is a wasteful number, since it uses less digits than its factorization.

688961853 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23964 (or 23961 counting only the distinct ones).

The product of its digits is 2488320, while the sum is 54.

The square root of 688961853 is about 26248.0828442765. The cubic root of 688961853 is about 883.2121985863.

The spelling of 688961853 in words is "six hundred eighty-eight million, nine hundred sixty-one thousand, eight hundred fifty-three".