679531891 has 4 divisors (see below), whose sum is σ = 686129392. Its totient is φ = 672934392.

The previous prime is 679531883. The next prime is 679531943. The reversal of 679531891 is 198135976.

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

It is a cyclic number.

It is not a de Polignac number, because 679531891 - 2³ = 679531883 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (679531291) 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 3 ways as a sum of consecutive naturals, for example, 3298596 + ... + 3298801.

It is an arithmetic number, because the mean of its divisors is an integer number (171532348).

Almost surely, 2^679531891 is an apocalyptic number.

679531891 is a deficient number, since it is larger than the sum of its proper divisors (6597501).

679531891 is a wasteful number, since it uses less digits than its factorization.

679531891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6597500.

The product of its digits is 408240, while the sum is 49.

The square root of 679531891 is about 26067.8324952421. The cubic root of 679531891 is about 879.1641042350.

The spelling of 679531891 in words is "six hundred seventy-nine million, five hundred thirty-one thousand, eight hundred ninety-one".