12642661644781 has 8 divisors (see below), whose sum is σ = 14693650338240. Its totient is φ = 10652896494528.

The previous prime is 12642661644733. The next prime is 12642661644829. The reversal of 12642661644781 is 18744616624621.

It is an interprime number because it is at equal distance from previous prime (12642661644733) and next prime (12642661644829).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12642661644781 - 2⁹ = 12642661644269 is a prime.

It is a super-2 number, since 2×12642661644781² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12642661644281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15305885356 + ... + 15305886181.

It is an arithmetic number, because the mean of its divisors is an integer number (1836706292280).

Almost surely, 2^{12642661644781} is an apocalyptic number.

It is an amenable number.

12642661644781 is a deficient number, since it is larger than the sum of its proper divisors (2050988693459).

12642661644781 is an equidigital number, since it uses as much as digits as its factorization.

12642661644781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30611771603.

The product of its digits is 18579456, while the sum is 58.

The spelling of 12642661644781 in words is "twelve trillion, six hundred forty-two billion, six hundred sixty-one million, six hundred forty-four thousand, seven hundred eighty-one".