206640625 has 27 divisors (see below), whose sum is σ = 270019393. Its totient is φ = 158125000.

The previous prime is 206640617. The next prime is 206640667. The reversal of 206640625 is 526046602.

The square root of 206640625 is 14375.

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 146918641 + 59721984 = 12121^2 + 7728^2 .

It is not a de Polignac number, because 206640625 - 2³ = 206640617 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 26 ways as a sum of consecutive naturals, for example, 8984364 + ... + 8984386.

Almost surely, 2^206640625 is an apocalyptic number.

206640625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

206640625 is the 14375-th square number.

206640625 is the 7188-th centered octagonal number.

It is an amenable number.

206640625 is a deficient number, since it is larger than the sum of its proper divisors (63378768).

206640625 is an frugal number, since it uses more digits than its factorization.

206640625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86 (or 28 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 31.

The cubic root of 206640625 is about 591.2056405536.

The spelling of 206640625 in words is "two hundred six million, six hundred forty thousand, six hundred twenty-five".