68256521 has 2 divisors, whose sum is σ = 68256522. Its totient is φ = 68256520.

The previous prime is 68256497. The next prime is 68256541. The reversal of 68256521 is 12565286.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 64176121 + 4080400 = 8011^2 + 2020^2 .

It is a cyclic number.

It is not a de Polignac number, because 68256521 - 2⁶ = 68256457 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (68256541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34128260 + 34128261.

It is an arithmetic number, because the mean of its divisors is an integer number (34128261).

Almost surely, 2^68256521 is an apocalyptic number.

It is an amenable number.

68256521 is a deficient number, since it is larger than the sum of its proper divisors (1).

68256521 is an equidigital number, since it uses as much as digits as its factorization.

68256521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 28800, while the sum is 35.

The square root of 68256521 is about 8261.7504803764. The cubic root of 68256521 is about 408.6781162733.

The spelling of 68256521 in words is "sixty-eight million, two hundred fifty-six thousand, five hundred twenty-one".