679857966225 has 135 divisors (see below), whose sum is σ = 1281926602209. Its totient is φ = 356199120000.

The previous prime is 679857966197. The next prime is 679857966233. The reversal of 679857966225 is 522669758976.

It is a happy number.

The square root of 679857966225 is 824535.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 3720146049 + 676137820176 = 60993^2 + 822276^2 .

It is a tau number, because it is divible by the number of its divisors (135).

It is not a de Polignac number, because 679857966225 - 2⁷ = 679857966097 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 134 ways as a sum of consecutive naturals, for example, 2708597350 + ... + 2708597600.

Almost surely, 2^679857966225 is an apocalyptic number.

679857966225 is the 824535-th square number.

679857966225 is the 412268-th centered octagonal number.

It is an amenable number.

679857966225 is a deficient number, since it is larger than the sum of its proper divisors (602068635984).

679857966225 is an frugal number, since it uses more digits than its factorization.

679857966225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 670 (or 332 counting only the distinct ones).

The product of its digits is 685843200, while the sum is 72.

The spelling of 679857966225 in words is "six hundred seventy-nine billion, eight hundred fifty-seven million, nine hundred sixty-six thousand, two hundred twenty-five".