68147243909 has 4 divisors (see below), whose sum is σ = 68269591404. Its totient is φ = 68024896416.

The previous prime is 68147243891. The next prime is 68147243929. The reversal of 68147243909 is 90934274186.

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 16082044225 + 52065199684 = 126815^2 + 228178^2 .

It is a cyclic number.

It is not a de Polignac number, because 68147243909 - 2⁸ = 68147243653 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 (68147243929) 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, 61172912 + ... + 61174025.

It is an arithmetic number, because the mean of its divisors is an integer number (17067397851).

Almost surely, 2^68147243909 is an apocalyptic number.

It is an amenable number.

68147243909 is a deficient number, since it is larger than the sum of its proper divisors (122347495).

68147243909 is a wasteful number, since it uses less digits than its factorization.

68147243909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122347494.

The product of its (nonzero) digits is 2612736, while the sum is 53.

The spelling of 68147243909 in words is "sixty-eight billion, one hundred forty-seven million, two hundred forty-three thousand, nine hundred nine".