979686223681 has 81 divisors (see below), whose sum is σ = 1176128666307. Its totient is φ = 815271050880.

The previous prime is 979686223673. The next prime is 979686223687. The reversal of 979686223681 is 186322686979.

The square root of 979686223681 is 989791.

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

979686223681 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 only one way, i.e., 762731489025 + 216954734656 = 873345^2 + 465784^2 .

It is not a de Polignac number, because 979686223681 - 2³ = 979686223673 is a prime.

It is a super-2 number, since 2×979686223681² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (67).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (979686223687) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 12401091400 + ... + 12401091478.

Almost surely, 2^979686223681 is an apocalyptic number.

979686223681 is the 989791-st square number.

979686223681 is the 494896-th centered octagonal number.

It is an amenable number.

979686223681 is a deficient number, since it is larger than the sum of its proper divisors (196442442626).

979686223681 is an equidigital number, since it uses as much as digits as its factorization.

979686223681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 348 (or 174 counting only the distinct ones).

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

The spelling of 979686223681 in words is "nine hundred seventy-nine billion, six hundred eighty-six million, two hundred twenty-three thousand, six hundred eighty-one".