68743521 has 72 divisors (see below), whose sum is σ = 129752064. Its totient is φ = 34655040.

The previous prime is 68743517. The next prime is 68743537. The reversal of 68743521 is 12534786.

68743521 is a `hidden beast` number, since 68 + 74 + 3 + 521 = 666.

It is not a de Polignac number, because 68743521 - 2² = 68743517 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (68743561) 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 71 ways as a sum of consecutive naturals, for example, 179296 + ... + 179678.

It is an arithmetic number, because the mean of its divisors is an integer number (1802112).

Almost surely, 2^68743521 is an apocalyptic number.

It is an amenable number.

68743521 is a deficient number, since it is larger than the sum of its proper divisors (61008543).

68743521 is a wasteful number, since it uses less digits than its factorization.

68743521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 451 (or 441 counting only the distinct ones).

The product of its digits is 40320, while the sum is 36.

The square root of 68743521 is about 8291.1712682829. The cubic root of 68743521 is about 409.6477660900.

The spelling of 68743521 in words is "sixty-eight million, seven hundred forty-three thousand, five hundred twenty-one".