68419388021 has 2 divisors, whose sum is σ = 68419388022. Its totient is φ = 68419388020.

The previous prime is 68419388017. The next prime is 68419388033. The reversal of 68419388021 is 12088391486.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 64480444900 + 3938943121 = 253930^2 + 62761^2 .

It is a cyclic number.

It is not a de Polignac number, because 68419388021 - 2² = 68419388017 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (68419388071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34209694010 + 34209694011.

It is an arithmetic number, because the mean of its divisors is an integer number (34209694011).

Almost surely, 2^68419388021 is an apocalyptic number.

It is an amenable number.

68419388021 is a deficient number, since it is larger than the sum of its proper divisors (1).

68419388021 is an equidigital number, since it uses as much as digits as its factorization.

68419388021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 663552, while the sum is 50.

The spelling of 68419388021 in words is "sixty-eight billion, four hundred nineteen million, three hundred eighty-eight thousand, twenty-one".