6999686158864 has 135 divisors (see below), whose sum is σ = 16049303417511. Its totient is φ = 2948782475520.

The previous prime is 6999686158819. The next prime is 6999686158867. The reversal of 6999686158864 is 4688516869996.

The square root of 6999686158864 is 2645692.

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

It can be written as a sum of positive squares in 4 ways, for example, as 3382995061264 + 3616691097600 = 1839292^2 + 1901760^2 .

It is not an unprimeable number, because it can be changed into a prime (6999686158867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 4518841162 + ... + 4518842710.

Almost surely, 2^{6999686158864} is an apocalyptic number.

6999686158864 is the 2645692-nd square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6999686158864

6999686158864 is an abundant number, since it is smaller than the sum of its proper divisors (9049617258647).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6999686158864 is an frugal number, since it uses more digits than its factorization.

6999686158864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3242 (or 1619 counting only the distinct ones).

The product of its digits is 9674588160, while the sum is 85.

The spelling of 6999686158864 in words is "six trillion, nine hundred ninety-nine billion, six hundred eighty-six million, one hundred fifty-eight thousand, eight hundred sixty-four".