68321391 has 4 divisors (see below), whose sum is σ = 91095192. Its totient is φ = 45547592.

The previous prime is 68321389. The next prime is 68321401. The reversal of 68321391 is 19312386.

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 68321391 - 2¹ = 68321389 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68321371) 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, 11386896 + ... + 11386901.

It is an arithmetic number, because the mean of its divisors is an integer number (22773798).

Almost surely, 2^68321391 is an apocalyptic number.

68321391 is a deficient number, since it is larger than the sum of its proper divisors (22773801).

68321391 is a wasteful number, since it uses less digits than its factorization.

68321391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22773800.

The product of its digits is 7776, while the sum is 33.

The square root of 68321391 is about 8265.6754714905. The cubic root of 68321391 is about 408.8075425167.

The spelling of 68321391 in words is "sixty-eight million, three hundred twenty-one thousand, three hundred ninety-one".