13200447721 has 4 divisors (see below), whose sum is σ = 13296801492. Its totient is φ = 13104093952.

The previous prime is 13200447649. The next prime is 13200447739. The reversal of 13200447721 is 12774400231.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 7445101225 + 5755346496 = 86285^2 + 75864^2 .

It is a cyclic number.

It is not a de Polignac number, because 13200447721 - 2⁹ = 13200447209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13200417721) 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, 48176680 + ... + 48176953.

It is an arithmetic number, because the mean of its divisors is an integer number (3324200373).

Almost surely, 2^13200447721 is an apocalyptic number.

It is an amenable number.

13200447721 is a deficient number, since it is larger than the sum of its proper divisors (96353771).

13200447721 is an equidigital number, since it uses as much as digits as its factorization.

13200447721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96353770.

The product of its (nonzero) digits is 9408, while the sum is 31.

Adding to 13200447721 its reverse (12774400231), we get a palindrome (25974847952).

The spelling of 13200447721 in words is "thirteen billion, two hundred million, four hundred forty-seven thousand, seven hundred twenty-one".