68405905 has 16 divisors (see below), whose sum is σ = 84839040. Its totient is φ = 52915968.

The previous prime is 68405903. The next prime is 68405921. The reversal of 68405905 is 50950486.

It is a cyclic number.

It is not a de Polignac number, because 68405905 - 2¹ = 68405903 is a prime.

It is not an unprimeable number, because it can be changed into a prime (68405903) 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 15 ways as a sum of consecutive naturals, for example, 20601 + ... + 23689.

It is an arithmetic number, because the mean of its divisors is an integer number (5302440).

Almost surely, 2^68405905 is an apocalyptic number.

It is an amenable number.

68405905 is a deficient number, since it is larger than the sum of its proper divisors (16433135).

68405905 is a wasteful number, since it uses less digits than its factorization.

68405905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3240.

The product of its (nonzero) digits is 43200, while the sum is 37.

The square root of 68405905 is about 8270.7862383210. The cubic root of 68405905 is about 408.9760389117.

The spelling of 68405905 in words is "sixty-eight million, four hundred five thousand, nine hundred five".