679745547977 has 4 divisors (see below), whose sum is σ = 689057130900. Its totient is φ = 670433965056.

The previous prime is 679745547959. The next prime is 679745547983. The reversal of 679745547977 is 779745547976.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 395554202761 + 284191345216 = 628931^2 + 533096^2 .

It is a cyclic number.

It is not a de Polignac number, because 679745547977 - 2¹⁶ = 679745482441 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 679745547898 and 679745547907.

It is not an unprimeable number, because it can be changed into a prime (679745547277) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4655791352 + ... + 4655791497.

It is an arithmetic number, because the mean of its divisors is an integer number (172264282725).

Almost surely, 2^679745547977 is an apocalyptic number.

It is an amenable number.

679745547977 is a deficient number, since it is larger than the sum of its proper divisors (9311582923).

679745547977 is an equidigital number, since it uses as much as digits as its factorization.

679745547977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9311582922.

The product of its digits is 3267280800, while the sum is 77.

Subtracting 679745547977 from its reverse (779745547976), we obtain a palindrome (99999999999).

The spelling of 679745547977 in words is "six hundred seventy-nine billion, seven hundred forty-five million, five hundred forty-seven thousand, nine hundred seventy-seven".