66031788936461 has 4 divisors (see below), whose sum is σ = 66062345064924. Its totient is φ = 66001232808000.

The previous prime is 66031788936427. The next prime is 66031788936479. The reversal of 66031788936461 is 16463988713066.

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 50148973580836 + 15882815355625 = 7081594^2 + 3985325^2 .

It is a cyclic number.

It is not a de Polignac number, because 66031788936461 - 2³⁰ = 66030715194637 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66031788936391 and 66031788936400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66031788936161) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15278060990 + ... + 15278065311.

It is an arithmetic number, because the mean of its divisors is an integer number (16515586266231).

Almost surely, 2^{66031788936461} is an apocalyptic number.

It is an amenable number.

66031788936461 is a deficient number, since it is larger than the sum of its proper divisors (30556128463).

66031788936461 is a wasteful number, since it uses less digits than its factorization.

66031788936461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30556128462.

The product of its (nonzero) digits is 188116992, while the sum is 68.

The spelling of 66031788936461 in words is "sixty-six trillion, thirty-one billion, seven hundred eighty-eight million, nine hundred thirty-six thousand, four hundred sixty-one".