68224139 has 4 divisors (see below), whose sum is σ = 68642856. Its totient is φ = 67805424.

The previous prime is 68224133. The next prime is 68224147. The reversal of 68224139 is 93142286.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-68224139 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 68224099 and 68224108.

It is not an unprimeable number, because it can be changed into a prime (68224133) 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, 209114 + ... + 209439.

It is an arithmetic number, because the mean of its divisors is an integer number (17160714).

Almost surely, 2^68224139 is an apocalyptic number.

68224139 is a deficient number, since it is larger than the sum of its proper divisors (418717).

68224139 is a wasteful number, since it uses less digits than its factorization.

68224139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 418716.

The product of its digits is 20736, while the sum is 35.

The square root of 68224139 is about 8259.7904937111. The cubic root of 68224139 is about 408.6134782094.

The spelling of 68224139 in words is "sixty-eight million, two hundred twenty-four thousand, one hundred thirty-nine".