2016721705 has 16 divisors (see below), whose sum is σ = 2447154000. Its totient is φ = 1595416320.

The previous prime is 2016721699. The next prime is 2016721711. The reversal of 2016721705 is 5071276102.

It is an interprime number because it is at equal distance from previous prime (2016721699) and next prime (2016721711).

It can be written as a sum of positive squares in 8 ways, for example, as 106419856 + 1910301849 = 10316^2 + 43707^2 .

It is not a de Polignac number, because 2016721705 - 2³ = 2016721697 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 164695 + ... + 176515.

It is an arithmetic number, because the mean of its divisors is an integer number (152947125).

Almost surely, 2^2016721705 is an apocalyptic number.

It is an amenable number.

2016721705 is a deficient number, since it is larger than the sum of its proper divisors (430432295).

2016721705 is a wasteful number, since it uses less digits than its factorization.

2016721705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12204.

The product of its (nonzero) digits is 5880, while the sum is 31.

The square root of 2016721705 is about 44907.9247460846. The cubic root of 2016721705 is about 1263.4226471914.

Adding to 2016721705 its reverse (5071276102), we get a palindrome (7087997807).

The spelling of 2016721705 in words is "two billion, sixteen million, seven hundred twenty-one thousand, seven hundred five".