13719651721 has 4 divisors (see below), whose sum is σ = 13796298000. Its totient is φ = 13643005444.

The previous prime is 13719651719. The next prime is 13719651749. The reversal of 13719651721 is 12715691731.

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 13719651721 - 2¹ = 13719651719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13719651221) 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, 38322871 + ... + 38323228.

It is an arithmetic number, because the mean of its divisors is an integer number (3449074500).

Almost surely, 2^13719651721 is an apocalyptic number.

It is an amenable number.

13719651721 is a deficient number, since it is larger than the sum of its proper divisors (76646279).

13719651721 is an equidigital number, since it uses as much as digits as its factorization.

13719651721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76646278.

The product of its digits is 79380, while the sum is 43.

The spelling of 13719651721 in words is "thirteen billion, seven hundred nineteen million, six hundred fifty-one thousand, seven hundred twenty-one".