68393621 has 2 divisors, whose sum is σ = 68393622. Its totient is φ = 68393620.

The previous prime is 68393609. The next prime is 68393623. The reversal of 68393621 is 12639386.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65383396 + 3010225 = 8086^2 + 1735^2 .

It is a cyclic number.

It is not a de Polignac number, because 68393621 - 2⁶ = 68393557 is a prime.

It is a Sophie Germain prime.

Together with 68393623, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (68393623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34196810 + 34196811.

It is an arithmetic number, because the mean of its divisors is an integer number (34196811).

Almost surely, 2^68393621 is an apocalyptic number.

It is an amenable number.

68393621 is a deficient number, since it is larger than the sum of its proper divisors (1).

68393621 is an equidigital number, since it uses as much as digits as its factorization.

68393621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 46656, while the sum is 38.

The square root of 68393621 is about 8270.0435911789. The cubic root of 68393621 is about 408.9515568029.

The spelling of 68393621 in words is "sixty-eight million, three hundred ninety-three thousand, six hundred twenty-one".