68064555491 has 4 divisors (see below), whose sum is σ = 68105338800. Its totient is φ = 68023772184.

The previous prime is 68064555463. The next prime is 68064555583. The reversal of 68064555491 is 19455546086.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 68064555491 - 2¹⁴ = 68064539107 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68064555401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20389151 + ... + 20392488.

It is an arithmetic number, because the mean of its divisors is an integer number (17026334700).

Almost surely, 2^68064555491 is an apocalyptic number.

68064555491 is a deficient number, since it is larger than the sum of its proper divisors (40783309).

68064555491 is a wasteful number, since it uses less digits than its factorization.

68064555491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40783308.

The product of its (nonzero) digits is 5184000, while the sum is 53.

The spelling of 68064555491 in words is "sixty-eight billion, sixty-four million, five hundred fifty-five thousand, four hundred ninety-one".