681311 has 2 divisors, whose sum is σ = 681312. Its totient is φ = 681310.

The previous prime is 681293. The next prime is 681337. The reversal of 681311 is 113186.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-681311 is a prime.

It is a Chen prime.

It is an Ulam number.

It is equal to p₅₅₁₆₃ and since 681311 and 55163 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (681341) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 340655 + 340656.

It is an arithmetic number, because the mean of its divisors is an integer number (340656).

2⁶⁸¹³¹¹ is an apocalyptic number.

681311 is a deficient number, since it is larger than the sum of its proper divisors (1).

681311 is an equidigital number, since it uses as much as digits as its factorization.

681311 is an evil number, because the sum of its binary digits is even.

The product of its digits is 144, while the sum is 20.

The square root of 681311 is about 825.4156528683. The cubic root of 681311 is about 87.9930693578.

Adding to 681311 its reverse (113186), we get a palindrome (794497).

The spelling of 681311 in words is "six hundred eighty-one thousand, three hundred eleven".