12000078721 has 4 divisors (see below), whose sum is σ = 12056951344. Its totient is φ = 11943206100.

The previous prime is 12000078689. The next prime is 12000078733. The reversal of 12000078721 is 12787000021.

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 12000078721 - 2⁵ = 12000078689 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 12000078721.

It is not an unprimeable number, because it can be changed into a prime (12000078221) 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, 28435995 + ... + 28436416.

It is an arithmetic number, because the mean of its divisors is an integer number (3014237836).

Almost surely, 2^12000078721 is an apocalyptic number.

It is an amenable number.

12000078721 is a deficient number, since it is larger than the sum of its proper divisors (56872623).

12000078721 is an equidigital number, since it uses as much as digits as its factorization.

12000078721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56872622.

The product of its (nonzero) digits is 1568, while the sum is 28.

Adding to 12000078721 its reverse (12787000021), we get a palindrome (24787078742).

The spelling of 12000078721 in words is "twelve billion, seventy-eight thousand, seven hundred twenty-one".