681051971 has 2 divisors, whose sum is σ = 681051972. Its totient is φ = 681051970.

The previous prime is 681051953. The next prime is 681052003. The reversal of 681051971 is 179150186.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 681051971 - 2²⁶ = 613943107 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (681051911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 340525985 + 340525986.

It is an arithmetic number, because the mean of its divisors is an integer number (340525986).

Almost surely, 2^681051971 is an apocalyptic number.

681051971 is a deficient number, since it is larger than the sum of its proper divisors (1).

681051971 is an equidigital number, since it uses as much as digits as its factorization.

681051971 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15120, while the sum is 38.

The square root of 681051971 is about 26096.9724489259. The cubic root of 681051971 is about 879.8191652353.

The spelling of 681051971 in words is "six hundred eighty-one million, fifty-one thousand, nine hundred seventy-one".