68139706 has 8 divisors (see below), whose sum is σ = 108221940. Its totient is φ = 32065728.

The previous prime is 68139703. The next prime is 68139713. The reversal of 68139706 is 60793186.

It can be written as a sum of positive squares in 2 ways, for example, as 67914081 + 225625 = 8241^2 + 475^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (68139703) 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, 1002021 + ... + 1002088.

Almost surely, 2^68139706 is an apocalyptic number.

68139706 is a deficient number, since it is larger than the sum of its proper divisors (40082234).

68139706 is a wasteful number, since it uses less digits than its factorization.

68139706 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2004128.

The product of its (nonzero) digits is 54432, while the sum is 40.

The square root of 68139706 is about 8254.6778253303. The cubic root of 68139706 is about 408.4448443286. Note that the first 3 decimals are identical.

The spelling of 68139706 in words is "sixty-eight million, one hundred thirty-nine thousand, seven hundred six".