13720078921 has 8 divisors (see below), whose sum is σ = 14240914688. Its totient is φ = 13204134000.

The previous prime is 13720078913. The next prime is 13720078963. The reversal of 13720078921 is 12987002731.

It is a happy number.

13720078921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 13720078921 - 2³ = 13720078913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13720078121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1216995 + ... + 1228216.

It is an arithmetic number, because the mean of its divisors is an integer number (1780114336).

Almost surely, 2^13720078921 is an apocalyptic number.

It is an amenable number.

13720078921 is a deficient number, since it is larger than the sum of its proper divisors (520835767).

13720078921 is a wasteful number, since it uses less digits than its factorization.

13720078921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2445423.

The product of its (nonzero) digits is 42336, while the sum is 40.

The spelling of 13720078921 in words is "thirteen billion, seven hundred twenty million, seventy-eight thousand, nine hundred twenty-one".