68708139 has 4 divisors (see below), whose sum is σ = 91610856. Its totient is φ = 45805424.

The previous prime is 68708137. The next prime is 68708173. The reversal of 68708139 is 93180786.

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 68708139 - 2¹ = 68708137 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 68708139.

It is not an unprimeable number, because it can be changed into a prime (68708131) 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, 11451354 + ... + 11451359.

It is an arithmetic number, because the mean of its divisors is an integer number (22902714).

Almost surely, 2^68708139 is an apocalyptic number.

68708139 is a deficient number, since it is larger than the sum of its proper divisors (22902717).

68708139 is a wasteful number, since it uses less digits than its factorization.

68708139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22902716.

The product of its (nonzero) digits is 72576, while the sum is 42.

The square root of 68708139 is about 8289.0372782368. The cubic root of 68708139 is about 409.5774727035.

The spelling of 68708139 in words is "sixty-eight million, seven hundred eight thousand, one hundred thirty-nine".