68257521 has 12 divisors (see below), whose sum is σ = 98859280. Its totient is φ = 45382680.

The previous prime is 68257507. The next prime is 68257549. The reversal of 68257521 is 12575286.

It is a happy number.

68257521 is a `hidden beast` number, since 6 + 82 + 57 + 521 = 666.

It is not a de Polignac number, because 68257521 - 2¹⁰ = 68256497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68257591) 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 in 11 ways as a sum of consecutive naturals, for example, 6595 + ... + 13416.

Almost surely, 2^68257521 is an apocalyptic number.

It is an amenable number.

68257521 is a deficient number, since it is larger than the sum of its proper divisors (30601759).

68257521 is a wasteful number, since it uses less digits than its factorization.

68257521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20396 (or 20393 counting only the distinct ones).

The product of its digits is 33600, while the sum is 36.

The square root of 68257521 is about 8261.8110000169. The cubic root of 68257521 is about 408.6801120588.

The spelling of 68257521 in words is "sixty-eight million, two hundred fifty-seven thousand, five hundred twenty-one".