12165684371781 has 64 divisors (see below), whose sum is σ = 16981373122560. Its totient is φ = 7741368391680.

The previous prime is 12165684371719. The next prime is 12165684371807. The reversal of 12165684371781 is 18717348656121.

It is a happy number.

It is not a de Polignac number, because 12165684371781 - 2³⁵ = 12131324633413 is a prime.

It is a super-2 number, since 2×12165684371781² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12165684371081) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 531914776 + ... + 531937646.

It is an arithmetic number, because the mean of its divisors is an integer number (265333955040).

Almost surely, 2^{12165684371781} is an apocalyptic number.

It is an amenable number.

12165684371781 is a deficient number, since it is larger than the sum of its proper divisors (4815688750779).

12165684371781 is a wasteful number, since it uses less digits than its factorization.

12165684371781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23546.

The product of its digits is 13547520, while the sum is 60.

The spelling of 12165684371781 in words is "twelve trillion, one hundred sixty-five billion, six hundred eighty-four million, three hundred seventy-one thousand, seven hundred eighty-one".