206565705025 has 27 divisors (see below), whose sum is σ = 272145819369. Its totient is φ = 155502737280.

The previous prime is 206565705023. The next prime is 206565705029. The reversal of 206565705025 is 520507565602.

The square root of 206565705025 is 454495.

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 4831779121 + 201733925904 = 69511^2 + 449148^2 .

It is not a de Polignac number, because 206565705025 - 2¹ = 206565705023 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (206565705023) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 38629402 + ... + 38634748.

Almost surely, 2^206565705025 is an apocalyptic number.

206565705025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

206565705025 is the 454495-th square number.

206565705025 is the 227248-th centered octagonal number.

It is an amenable number.

206565705025 is a deficient number, since it is larger than the sum of its proper divisors (65580114344).

206565705025 is an frugal number, since it uses more digits than its factorization.

206565705025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10738 (or 5369 counting only the distinct ones).

The product of its (nonzero) digits is 630000, while the sum is 43.

The spelling of 206565705025 in words is "two hundred six billion, five hundred sixty-five million, seven hundred five thousand, twenty-five".