679666581 has 12 divisors (see below), whose sum is σ = 1070989920. Its totient is φ = 411919080.

The previous prime is 679666571. The next prime is 679666597. The reversal of 679666581 is 185666976.

It is not a de Polignac number, because 679666581 - 2¹¹ = 679664533 is a prime.

It is a super-2 number, since 2×679666581² = 923893322656459122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (679666531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3432561 + ... + 3432758.

It is an arithmetic number, because the mean of its divisors is an integer number (89249160).

Almost surely, 2^679666581 is an apocalyptic number.

It is an amenable number.

679666581 is a deficient number, since it is larger than the sum of its proper divisors (391323339).

679666581 is a wasteful number, since it uses less digits than its factorization.

679666581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6865336 (or 6865333 counting only the distinct ones).

The product of its digits is 3265920, while the sum is 54.

The square root of 679666581 is about 26070.4158194686. The cubic root of 679666581 is about 879.2221867630. Note that the first 3 decimals are identical.

It can be divided in two parts, 67966 and 6581, that added together give a palindrome (74547).

The spelling of 679666581 in words is "six hundred seventy-nine million, six hundred sixty-six thousand, five hundred eighty-one".