68431985 has 4 divisors (see below), whose sum is σ = 82118388. Its totient is φ = 54745584.

The previous prime is 68431931. The next prime is 68431997. The reversal of 68431985 is 58913486.

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 45859984 + 22572001 = 6772^2 + 4751^2 .

It is a cyclic number.

It is not a de Polignac number, because 68431985 - 2¹⁴ = 68415601 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6843194 + ... + 6843203.

It is an arithmetic number, because the mean of its divisors is an integer number (20529597).

Almost surely, 2^68431985 is an apocalyptic number.

It is an amenable number.

68431985 is a deficient number, since it is larger than the sum of its proper divisors (13686403).

68431985 is a wasteful number, since it uses less digits than its factorization.

68431985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13686402.

The product of its digits is 207360, while the sum is 44.

The square root of 68431985 is about 8272.3627217380. The cubic root of 68431985 is about 409.0280068419.

The spelling of 68431985 in words is "sixty-eight million, four hundred thirty-one thousand, nine hundred eighty-five".