205621825 has 12 divisors (see below), whose sum is σ = 255368700. Its totient is φ = 164240960.

The previous prime is 205621813. The next prime is 205621831. The reversal of 205621825 is 528126502.

It can be written as a sum of positive squares in 6 ways, for example, as 54626881 + 150994944 = 7391^2 + 12288^2 .

It is not a de Polignac number, because 205621825 - 2⁷ = 205621697 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10851 + ... + 22999.

It is an arithmetic number, because the mean of its divisors is an integer number (21280725).

Almost surely, 2^205621825 is an apocalyptic number.

205621825 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

205621825 is a deficient number, since it is larger than the sum of its proper divisors (49746875).

205621825 is a wasteful number, since it uses less digits than its factorization.

205621825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12836 (or 12831 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 31.

The square root of 205621825 is about 14339.5196920957. The cubic root of 205621825 is about 590.2324325992.

The spelling of 205621825 in words is "two hundred five million, six hundred twenty-one thousand, eight hundred twenty-five".