68513409 has 6 divisors (see below), whose sum is σ = 98963826. Its totient is φ = 45675600.

The previous prime is 68513377. The next prime is 68513443. The reversal of 68513409 is 90431586.

It can be written as a sum of positive squares in only one way, i.e., 64400625 + 4112784 = 8025^2 + 2028^2 .

It is not a de Polignac number, because 68513409 - 2⁵ = 68513377 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (68513479) 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 5 ways as a sum of consecutive naturals, for example, 3806292 + ... + 3806309.

It is an arithmetic number, because the mean of its divisors is an integer number (16493971).

Almost surely, 2^68513409 is an apocalyptic number.

It is an amenable number.

68513409 is a deficient number, since it is larger than the sum of its proper divisors (30450417).

68513409 is a wasteful number, since it uses less digits than its factorization.

68513409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7612607 (or 7612604 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 68513409 is about 8277.2827062992. The cubic root of 68513409 is about 409.1901702704.

The spelling of 68513409 in words is "sixty-eight million, five hundred thirteen thousand, four hundred nine".