68215913 has 4 divisors (see below), whose sum is σ = 68289348. Its totient is φ = 68142480.

The previous prime is 68215879. The next prime is 68215937. The reversal of 68215913 is 31951286.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 45050944 + 23164969 = 6712^2 + 4813^2 .

It is a cyclic number.

It is not a de Polignac number, because 68215913 - 2¹⁰ = 68214889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68215943) 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, 35306 + ... + 37187.

It is an arithmetic number, because the mean of its divisors is an integer number (17072337).

Almost surely, 2^68215913 is an apocalyptic number.

It is an amenable number.

68215913 is a deficient number, since it is larger than the sum of its proper divisors (73435).

68215913 is an equidigital number, since it uses as much as digits as its factorization.

68215913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73434.

The product of its digits is 12960, while the sum is 35.

The square root of 68215913 is about 8259.2925241815. The cubic root of 68215913 is about 408.5970549433.

The spelling of 68215913 in words is "sixty-eight million, two hundred fifteen thousand, nine hundred thirteen".