679571657 has 4 divisors (see below), whose sum is σ = 680194500. Its totient is φ = 678948816.

The previous prime is 679571591. The next prime is 679571701. The reversal of 679571657 is 756175976.

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 517289536 + 162282121 = 22744^2 + 12739^2 .

It is a cyclic number.

It is not a de Polignac number, because 679571657 - 2⁸ = 679571401 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 679571599 and 679571608.

It is not an unprimeable number, because it can be changed into a prime (679571257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 309782 + ... + 311967.

It is an arithmetic number, because the mean of its divisors is an integer number (170048625).

Almost surely, 2^679571657 is an apocalyptic number.

It is an amenable number.

679571657 is a deficient number, since it is larger than the sum of its proper divisors (622843).

679571657 is a wasteful number, since it uses less digits than its factorization.

679571657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 622842.

The product of its digits is 2778300, while the sum is 53.

The square root of 679571657 is about 26068.5952249062. The cubic root of 679571657 is about 879.1812533726.

The spelling of 679571657 in words is "six hundred seventy-nine million, five hundred seventy-one thousand, six hundred fifty-seven".