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688861 is a prime number
BaseRepresentation
bin10101000001011011101
31021222221101
42220023131
5134020421
622433101
75566225
oct2501335
91258841
10688861
11430608
12292791
131b1714
1413d085
15d9191
hexa82dd

688861 has 2 divisors, whose sum is σ = 688862. Its totient is φ = 688860.

The previous prime is 688813. The next prime is 688867. The reversal of 688861 is 168886.

688861 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 656100 + 32761 = 810^2 + 181^2 .

It is a cyclic number.

It is not a de Polignac number, because 688861 - 27 = 688733 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 688861.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (688867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344430 + 344431.

It is an arithmetic number, because the mean of its divisors is an integer number (344431).

2688861 is an apocalyptic number.

It is an amenable number.

688861 is a deficient number, since it is larger than the sum of its proper divisors (1).

688861 is an equidigital number, since it uses as much as digits as its factorization.

688861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18432, while the sum is 37.

The square root of 688861 is about 829.9765056916. The cubic root of 688861 is about 88.3169100435.

The spelling of 688861 in words is "six hundred eighty-eight thousand, eight hundred sixty-one".