68139170813 has 4 divisors (see below), whose sum is σ = 77873338080. Its totient is φ = 58405003548.

The previous prime is 68139170761. The next prime is 68139170833. The reversal of 68139170813 is 31807193186.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 68139170813 - 2²⁰ = 68138122237 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68139170833) 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, 4867083623 + ... + 4867083636.

It is an arithmetic number, because the mean of its divisors is an integer number (19468334520).

Almost surely, 2^68139170813 is an apocalyptic number.

It is an amenable number.

68139170813 is a deficient number, since it is larger than the sum of its proper divisors (9734167267).

68139170813 is an equidigital number, since it uses as much as digits as its factorization.

68139170813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9734167266.

The product of its (nonzero) digits is 217728, while the sum is 47.

The spelling of 68139170813 in words is "sixty-eight billion, one hundred thirty-nine million, one hundred seventy thousand, eight hundred thirteen".