67716781553 has 4 divisors (see below), whose sum is σ = 68826892788. Its totient is φ = 66606670320.

The previous prime is 67716781487. The next prime is 67716781597. The reversal of 67716781553 is 35518761776.

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 19916830129 + 47799951424 = 141127^2 + 218632^2 .

It is a cyclic number.

It is not a de Polignac number, because 67716781553 - 2²⁶ = 67649672689 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (67716780553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 555055526 + ... + 555055647.

It is an arithmetic number, because the mean of its divisors is an integer number (17206723197).

Almost surely, 2^67716781553 is an apocalyptic number.

It is an amenable number.

67716781553 is a deficient number, since it is larger than the sum of its proper divisors (1110111235).

67716781553 is a wasteful number, since it uses less digits than its factorization.

67716781553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1110111234.

The product of its digits is 7408800, while the sum is 56.

The spelling of 67716781553 in words is "sixty-seven billion, seven hundred sixteen million, seven hundred eighty-one thousand, five hundred fifty-three".