2176838721 has 12 divisors (see below), whose sum is σ = 3309813520. Its totient is φ = 1374845400.

The previous prime is 2176838711. The next prime is 2176838747. The reversal of 2176838721 is 1278386712.

2176838721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 2176838721 - 2¹⁴ = 2176822337 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2176838711) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6364855 + ... + 6365196.

Almost surely, 2^2176838721 is an apocalyptic number.

It is an amenable number.

2176838721 is a deficient number, since it is larger than the sum of its proper divisors (1132974799).

2176838721 is a wasteful number, since it uses less digits than its factorization.

2176838721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12730076 (or 12730073 counting only the distinct ones).

The product of its digits is 225792, while the sum is 45.

The square root of 2176838721 is about 46656.6042592043. The cubic root of 2176838721 is about 1296.0111899611.

The spelling of 2176838721 in words is "two billion, one hundred seventy-six million, eight hundred thirty-eight thousand, seven hundred twenty-one".