12646688664621 has 64 divisors (see below), whose sum is σ = 18834019430400. Its totient is φ = 7483309616640.

The previous prime is 12646688664619. The next prime is 12646688664707.

It is a happy number.

12646688664621 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 12646688664621 - 2¹ = 12646688664619 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12646688664521) 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, 327895480 + ... + 327934046.

It is an arithmetic number, because the mean of its divisors is an integer number (294281553600).

Almost surely, 2^{12646688664621} is an apocalyptic number.

12646688664621 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12646688664621 is a deficient number, since it is larger than the sum of its proper divisors (6187330765779).

12646688664621 is a wasteful number, since it uses less digits than its factorization.

12646688664621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39546.

The product of its digits is 191102976, while the sum is 66.

The spelling of 12646688664621 in words is "twelve trillion, six hundred forty-six billion, six hundred eighty-eight million, six hundred sixty-four thousand, six hundred twenty-one".