2163449721 has 8 divisors (see below), whose sum is σ = 2884888224. Its totient is φ = 1442155520.

The previous prime is 2163449719. The next prime is 2163449777. The reversal of 2163449721 is 1279443612.

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 2163449721 - 2¹ = 2163449719 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2163449721.

It is not an unprimeable number, because it can be changed into a prime (2163449711) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5881 + ... + 66041.

It is an arithmetic number, because the mean of its divisors is an integer number (360611028).

Almost surely, 2^2163449721 is an apocalyptic number.

It is an amenable number.

2163449721 is a deficient number, since it is larger than the sum of its proper divisors (721438503).

2163449721 is a wasteful number, since it uses less digits than its factorization.

2163449721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72151.

The product of its digits is 72576, while the sum is 39.

The square root of 2163449721 is about 46512.8984368852. The cubic root of 2163449721 is about 1293.3486145249.

The spelling of 2163449721 in words is "two billion, one hundred sixty-three million, four hundred forty-nine thousand, seven hundred twenty-one".