68144539 has 4 divisors (see below), whose sum is σ = 68359824. Its totient is φ = 67929256.

The previous prime is 68144533. The next prime is 68144567. The reversal of 68144539 is 93544186.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 68144539 - 2¹³ = 68136347 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68144533) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 107167 + ... + 107800.

It is an arithmetic number, because the mean of its divisors is an integer number (17089956).

Almost surely, 2^68144539 is an apocalyptic number.

68144539 is a deficient number, since it is larger than the sum of its proper divisors (215285).

68144539 is a wasteful number, since it uses less digits than its factorization.

68144539 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 215284.

The product of its digits is 103680, while the sum is 40.

The square root of 68144539 is about 8254.9705632425. The cubic root of 68144539 is about 408.4545007994.

The spelling of 68144539 in words is "sixty-eight million, one hundred forty-four thousand, five hundred thirty-nine".