16721512145 has 16 divisors (see below), whose sum is σ = 21728742672. Its totient is φ = 12279962880.

The previous prime is 16721512139. The next prime is 16721512183. The reversal of 16721512145 is 54121512761.

16721512145 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 8 ways, for example, as 4695538576 + 12025973569 = 68524^2 + 109663^2 .

It is not a de Polignac number, because 16721512145 - 2¹⁴ = 16721495761 is a prime.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 698882 + ... + 722411.

It is an arithmetic number, because the mean of its divisors is an integer number (1358046417).

Almost surely, 2^16721512145 is an apocalyptic number.

It is an amenable number.

16721512145 is a deficient number, since it is larger than the sum of its proper divisors (5007230527).

16721512145 is a wasteful number, since it uses less digits than its factorization.

16721512145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1421492.

The product of its digits is 16800, while the sum is 35.

The spelling of 16721512145 in words is "sixteen billion, seven hundred twenty-one million, five hundred twelve thousand, one hundred forty-five".