16864398769 has 9 divisors (see below), whose sum is σ = 17917122027. Its totient is φ = 15870297504.

The previous prime is 16864398763. The next prime is 16864398773. The reversal of 16864398769 is 96789346861.

The square root of 16864398769 is 129863.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 13129722225 + 3734676544 = 114585^2 + 61112^2 .

It is a de Polignac number, because none of the positive numbers 2^k-16864398769 is a prime.

It is a super-2 number, since 2×16864398769² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16864398763) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 2203852 + ... + 2211490.

Almost surely, 2^16864398769 is an apocalyptic number.

16864398769 is the 129863-rd square number.

16864398769 is the 64932-nd centered octagonal number.

It is an amenable number.

16864398769 is a deficient number, since it is larger than the sum of its proper divisors (1052723258).

16864398769 is an frugal number, since it uses more digits than its factorization.

16864398769 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15312 (or 7656 counting only the distinct ones).

The product of its digits is 94058496, while the sum is 67.

The spelling of 16864398769 in words is "sixteen billion, eight hundred sixty-four million, three hundred ninety-eight thousand, seven hundred sixty-nine".