66665051534161 has 4 divisors (see below), whose sum is σ = 67106541941824. Its totient is φ = 66223561126500.

The previous prime is 66665051534143. The next prime is 66665051534173. The reversal of 66665051534161 is 16143515056666.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 66665051534161 - 2²⁷ = 66664917316433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66665051531161) 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, 220745203605 + ... + 220745203906.

It is an arithmetic number, because the mean of its divisors is an integer number (16776635485456).

Almost surely, 2^{66665051534161} is an apocalyptic number.

It is an amenable number.

66665051534161 is a deficient number, since it is larger than the sum of its proper divisors (441490407663).

66665051534161 is a wasteful number, since it uses less digits than its factorization.

66665051534161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 441490407662.

The product of its (nonzero) digits is 11664000, while the sum is 55.

The spelling of 66665051534161 in words is "sixty-six trillion, six hundred sixty-five billion, fifty-one million, five hundred thirty-four thousand, one hundred sixty-one".