684946588225 has 9 divisors (see below), whose sum is σ = 849338900643. Its totient is φ = 547953960120.

The previous prime is 684946588217. The next prime is 684946588231. The reversal of 684946588225 is 522885649486.

The square root of 684946588225 is 827615.

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

It can be written as a sum of positive squares in only one way, i.e., 246580771761 + 438365816464 = 496569^2 + 662092^2 .

It is not a de Polignac number, because 684946588225 - 2³ = 684946588217 is a prime.

It is a super-3 number, since 3×684946588225³ (a number of 36 digits) contains 333 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 4055314 + ... + 4220836.

Almost surely, 2^684946588225 is an apocalyptic number.

684946588225 is the 827615-th square number.

684946588225 is the 413808-th centered octagonal number.

It is an amenable number.

684946588225 is a deficient number, since it is larger than the sum of its proper divisors (164392312418).

684946588225 is an frugal number, since it uses more digits than its factorization.

684946588225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 331056 (or 165528 counting only the distinct ones).

The product of its digits is 265420800, while the sum is 67.

The spelling of 684946588225 in words is "six hundred eighty-four billion, nine hundred forty-six million, five hundred eighty-eight thousand, two hundred twenty-five".