68006665 has 4 divisors (see below), whose sum is σ = 81608004. Its totient is φ = 54405328.

The previous prime is 68006657. The next prime is 68006669. The reversal of 68006665 is 56660086.

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 39137536 + 28869129 = 6256^2 + 5373^2 .

It is a cyclic number.

It is not a de Polignac number, because 68006665 - 2³ = 68006657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68006669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6800662 + ... + 6800671.

It is an arithmetic number, because the mean of its divisors is an integer number (20402001).

Almost surely, 2^68006665 is an apocalyptic number.

It is an amenable number.

68006665 is a deficient number, since it is larger than the sum of its proper divisors (13601339).

68006665 is a wasteful number, since it uses less digits than its factorization.

68006665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13601338.

The product of its (nonzero) digits is 51840, while the sum is 37.

The square root of 68006665 is about 8246.6153663185. The cubic root of 68006665 is about 408.1788451635.

The spelling of 68006665 in words is "sixty-eight million, six thousand, six hundred sixty-five".