681068449 has 2 divisors, whose sum is σ = 681068450. Its totient is φ = 681068448.

The previous prime is 681068441. The next prime is 681068461. The reversal of 681068449 is 944860186.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 677040400 + 4028049 = 26020^2 + 2007^2 .

It is a cyclic number.

It is not a de Polignac number, because 681068449 - 2³ = 681068441 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 681068399 and 681068408.

It is not a weakly prime, because it can be changed into another prime (681068441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 340534224 + 340534225.

It is an arithmetic number, because the mean of its divisors is an integer number (340534225).

Almost surely, 2^681068449 is an apocalyptic number.

It is an amenable number.

681068449 is a deficient number, since it is larger than the sum of its proper divisors (1).

681068449 is an equidigital number, since it uses as much as digits as its factorization.

681068449 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 331776, while the sum is 46.

The square root of 681068449 is about 26097.2881541359. The cubic root of 681068449 is about 879.8262608971.

The spelling of 681068449 in words is "six hundred eighty-one million, sixty-eight thousand, four hundred forty-nine".