680161 has 2 divisors, whose sum is σ = 680162. Its totient is φ = 680160.

The previous prime is 680159. The next prime is 680177. The reversal of 680161 is 161086.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 483025 + 197136 = 695^2 + 444^2 .

It is a cyclic number.

It is not a de Polignac number, because 680161 - 2¹ = 680159 is a prime.

Together with 680159, it forms a pair of twin primes.

680161 is a lucky number.

It is equal to p₅₅₀₇₅ and since 680161 and 55075 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (680861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 340080 + 340081.

It is an arithmetic number, because the mean of its divisors is an integer number (340081).

2⁶⁸⁰¹⁶¹ is an apocalyptic number.

It is an amenable number.

680161 is a deficient number, since it is larger than the sum of its proper divisors (1).

680161 is an equidigital number, since it uses as much as digits as its factorization.

680161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 22.

The square root of 680161 is about 824.7187399350. The cubic root of 680161 is about 87.9435329894.

It can be divided in two parts, 680 and 161, that added together give a square (841 = 29²).

The spelling of 680161 in words is "six hundred eighty thousand, one hundred sixty-one".