679431638 has 16 divisors (see below), whose sum is σ = 1064369376. Its totient is φ = 324667200.

The previous prime is 679431617. The next prime is 679431647. The reversal of 679431638 is 836134976.

It is a happy number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 679431592 and 679431601.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54170 + ... + 65522.

It is an arithmetic number, because the mean of its divisors is an integer number (66523086).

Almost surely, 2^679431638 is an apocalyptic number.

679431638 is a deficient number, since it is larger than the sum of its proper divisors (384937738).

679431638 is a wasteful number, since it uses less digits than its factorization.

679431638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12679.

The product of its digits is 653184, while the sum is 47.

The square root of 679431638 is about 26065.9094988071. The cubic root of 679431638 is about 879.1208670326.

The spelling of 679431638 in words is "six hundred seventy-nine million, four hundred thirty-one thousand, six hundred thirty-eight".