68644513 has 4 divisors (see below), whose sum is σ = 78450880. Its totient is φ = 58838148.

The previous prime is 68644507. The next prime is 68644517. The reversal of 68644513 is 31544686.

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 not a de Polignac number, because 68644513 - 2⁹ = 68644001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68644517) 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, 4903173 + ... + 4903186.

It is an arithmetic number, because the mean of its divisors is an integer number (19612720).

Almost surely, 2^68644513 is an apocalyptic number.

It is an amenable number.

68644513 is a deficient number, since it is larger than the sum of its proper divisors (9806367).

68644513 is an equidigital number, since it uses as much as digits as its factorization.

68644513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9806366.

The product of its digits is 69120, while the sum is 37.

The square root of 68644513 is about 8285.1984285230. The cubic root of 68644513 is about 409.4510062476.

The spelling of 68644513 in words is "sixty-eight million, six hundred forty-four thousand, five hundred thirteen".