12358664817721 has 4 divisors (see below), whose sum is σ = 12358675515472. Its totient is φ = 12358654119972.

The previous prime is 12358664817701. The next prime is 12358664817761. The reversal of 12358664817721 is 12771846685321.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 12358664817721 - 2¹⁵ = 12358664784953 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12358664817721.

It is not an unprimeable number, because it can be changed into a prime (12358664817701) 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, 3372591 + ... + 6007636.

It is an arithmetic number, because the mean of its divisors is an integer number (3089668878868).

Almost surely, 2^{12358664817721} is an apocalyptic number.

It is an amenable number.

12358664817721 is a deficient number, since it is larger than the sum of its proper divisors (10697751).

12358664817721 is an equidigital number, since it uses as much as digits as its factorization.

12358664817721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10697750.

The product of its digits is 27095040, while the sum is 61.

The spelling of 12358664817721 in words is "twelve trillion, three hundred fifty-eight billion, six hundred sixty-four million, eight hundred seventeen thousand, seven hundred twenty-one".