205625021 has 12 divisors (see below), whose sum is σ = 245663388. Its totient is φ = 171484992.

The previous prime is 205624987. The next prime is 205625023. The reversal of 205625021 is 120526502.

205625021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 113656921 + 91968100 = 10661^2 + 9590^2 .

It is not a de Polignac number, because 205625021 - 2²² = 201430717 is a prime.

It is a super-2 number, since 2×205625021² = 84563298522500882, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205625023) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 54896 + ... + 58521.

It is an arithmetic number, because the mean of its divisors is an integer number (20471949).

Almost surely, 2^205625021 is an apocalyptic number.

It is an amenable number.

205625021 is a deficient number, since it is larger than the sum of its proper divisors (40038367).

205625021 is a wasteful number, since it uses less digits than its factorization.

205625021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113468 (or 113461 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 205625021 is about 14339.6311319364. The cubic root of 205625021 is about 590.2354905967.

The spelling of 205625021 in words is "two hundred five million, six hundred twenty-five thousand, twenty-one".