16938270721 has 4 divisors (see below), whose sum is σ = 17008554244. Its totient is φ = 16867987200.

The previous prime is 16938270707. The next prime is 16938270731. The reversal of 16938270721 is 12707283961.

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 12192576400 + 4745694321 = 110420^2 + 68889^2 .

It is a cyclic number.

It is not a de Polignac number, because 16938270721 - 2²⁹ = 16401399809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16938270731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35141400 + ... + 35141881.

It is an arithmetic number, because the mean of its divisors is an integer number (4252138561).

Almost surely, 2^16938270721 is an apocalyptic number.

It is an amenable number.

16938270721 is a deficient number, since it is larger than the sum of its proper divisors (70283523).

16938270721 is an equidigital number, since it uses as much as digits as its factorization.

16938270721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70283522.

The product of its (nonzero) digits is 254016, while the sum is 46.

The spelling of 16938270721 in words is "sixteen billion, nine hundred thirty-eight million, two hundred seventy thousand, seven hundred twenty-one".