205263661 has 8 divisors (see below), whose sum is σ = 226787904. Its totient is φ = 184789440.

The previous prime is 205263649. The next prime is 205263683. The reversal of 205263661 is 166362502.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 205263661 - 2¹⁹ = 204739373 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205263601) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 262095 + ... + 262876.

It is an arithmetic number, because the mean of its divisors is an integer number (28348488).

Almost surely, 2^205263661 is an apocalyptic number.

It is an amenable number.

205263661 is a deficient number, since it is larger than the sum of its proper divisors (21524243).

205263661 is a wasteful number, since it uses less digits than its factorization.

205263661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 525011.

The product of its (nonzero) digits is 12960, while the sum is 31.

The square root of 205263661 is about 14327.0255461488. The cubic root of 205263661 is about 589.8895330864.

The spelling of 205263661 in words is "two hundred five million, two hundred sixty-three thousand, six hundred sixty-one".