689688617 has 2 divisors, whose sum is σ = 689688618. Its totient is φ = 689688616.

The previous prime is 689688539. The next prime is 689688683. The reversal of 689688617 is 716886986.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 666465856 + 23222761 = 25816^2 + 4819^2 .

It is a cyclic number.

It is not a de Polignac number, because 689688617 - 2¹⁴ = 689672233 is a prime.

It is a super-3 number, since 3×689688617³ (a number of 27 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (689684617) 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 as a sum of consecutive naturals, namely, 344844308 + 344844309.

It is an arithmetic number, because the mean of its divisors is an integer number (344844309).

Almost surely, 2^689688617 is an apocalyptic number.

It is an amenable number.

689688617 is a deficient number, since it is larger than the sum of its proper divisors (1).

689688617 is an equidigital number, since it uses as much as digits as its factorization.

689688617 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6967296, while the sum is 59.

The square root of 689688617 is about 26261.9233301752. The cubic root of 689688617 is about 883.5226469600.

The spelling of 689688617 in words is "six hundred eighty-nine million, six hundred eighty-eight thousand, six hundred seventeen".