68509643 has 4 divisors (see below), whose sum is σ = 72539640. Its totient is φ = 64479648.

The previous prime is 68509633. The next prime is 68509667. The reversal of 68509643 is 34690586.

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 68509643 - 2⁴ = 68509627 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 68509643.

It is not an unprimeable number, because it can be changed into a prime (68509603) 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, 2014973 + ... + 2015006.

It is an arithmetic number, because the mean of its divisors is an integer number (18134910).

Almost surely, 2^68509643 is an apocalyptic number.

68509643 is a deficient number, since it is larger than the sum of its proper divisors (4029997).

68509643 is a wasteful number, since it uses less digits than its factorization.

68509643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4029996.

The product of its (nonzero) digits is 155520, while the sum is 41.

The square root of 68509643 is about 8277.0552130574. The cubic root of 68509643 is about 409.1826727676.

The spelling of 68509643 in words is "sixty-eight million, five hundred nine thousand, six hundred forty-three".