2068351721 has 2 divisors, whose sum is σ = 2068351722. Its totient is φ = 2068351720.

The previous prime is 2068351697. The next prime is 2068351759. The reversal of 2068351721 is 1271538602.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1913100121 + 155251600 = 43739^2 + 12460^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2068351721 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (2068351771) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1034175860 + 1034175861.

It is an arithmetic number, because the mean of its divisors is an integer number (1034175861).

Almost surely, 2^2068351721 is an apocalyptic number.

It is an amenable number.

2068351721 is a deficient number, since it is larger than the sum of its proper divisors (1).

2068351721 is an equidigital number, since it uses as much as digits as its factorization.

2068351721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20160, while the sum is 35.

The square root of 2068351721 is about 45479.1350071656. The cubic root of 2068351721 is about 1274.1135390926.

The spelling of 2068351721 in words is "two billion, sixty-eight million, three hundred fifty-one thousand, seven hundred twenty-one".