68809813 has 4 divisors (see below), whose sum is σ = 71801568. Its totient is φ = 65818060.

The previous prime is 68809799. The next prime is 68809817. The reversal of 68809813 is 31890886.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-68809813 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 68809813.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68809817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1495843 + ... + 1495888.

It is an arithmetic number, because the mean of its divisors is an integer number (17950392).

Almost surely, 2^68809813 is an apocalyptic number.

It is an amenable number.

68809813 is a deficient number, since it is larger than the sum of its proper divisors (2991755).

68809813 is a wasteful number, since it uses less digits than its factorization.

68809813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2991754.

The product of its (nonzero) digits is 82944, while the sum is 43.

The square root of 68809813 is about 8295.1680513417. The cubic root of 68809813 is about 409.7794034413.

The spelling of 68809813 in words is "sixty-eight million, eight hundred nine thousand, eight hundred thirteen".