681123559 has 2 divisors, whose sum is σ = 681123560. Its totient is φ = 681123558.

The previous prime is 681123473. The next prime is 681123563. The reversal of 681123559 is 955321186.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 681123559 - 2⁷ = 681123431 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (681123259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 340561779 + 340561780.

It is an arithmetic number, because the mean of its divisors is an integer number (340561780).

Almost surely, 2^681123559 is an apocalyptic number.

681123559 is a deficient number, since it is larger than the sum of its proper divisors (1).

681123559 is an equidigital number, since it uses as much as digits as its factorization.

681123559 is an evil number, because the sum of its binary digits is even.

The product of its digits is 64800, while the sum is 40.

The square root of 681123559 is about 26098.3439896098. The cubic root of 681123559 is about 879.8499912175.

The spelling of 681123559 in words is "six hundred eighty-one million, one hundred twenty-three thousand, five hundred fifty-nine".